Land Management Field Manual - Crow's Nest · This manual identifies (Map 3) and describes the land resource areas for the Crew's Nest district, and collates all available information

CROWS NEST DISTRICTCROWS NEST DISTRICT

LAND MANAGEMENT

FIELD MANUAL

LAND MANAGEMENT LAND MANAGEMENT

FIELD MANUAL FIELD MANUAL

QE83001

Queensland Government Technical Report

This report is a scanned copy and some detail may be illegible or lost. Before acting on any

information, readers are strongly advised to ensure that numerals, percentages and details are correct.

This report is intended to provide information only on the subject under review. There are limitations

inherent in land resource studies, such as accuracy in relation to map scale and assumptions regarding

socio-economic factors for land evaluation. Before acting on the information conveyed in this report,

readers should ensure that they have received adequate professional information and advice specific to

their enquiry.

While all care has been taken in the preparation of this report neither the Queensland Government nor

its officers or staff accepts any responsibility for any loss or damage that may result from any

inaccuracy or omission in the information contained herein.

© State of Queensland 1983

For information about this report contact [email protected]

Queensland Department of Primary Industries

Training Series Q£83001

LAND MANAGEMENT FIELD MANUAL

CROW'S NEST DISTRICT

J. Bierenbroodspot Soil Conservation Branch

Major contributor

and

J.A. Mullins Development Planning Branch

Editor

Queensland Department of Primary Industries Brisbane 1983

ISSN 0812-0005

None of the material contained in this publication may be abstracted or cited as a reference without the specific permission of the authors concerned.

Queensland Department of Primary Industries

GPO Box 46

Brisbane 4001.

(\)

�·

Pittsworth

SCALE 1:1 000 000

LEGEND Road

Railway

Soil Conservation Study Area r--, L __ J

'i:·�_-·::f <

CON, �� ,

. . ·> . I'Vol\'o . �,. .

;, · ' · · . '41.£ ' .

-�/I /, ' /,

onah

QUEENSLAND

DEPARTMENT OF PRIMARY INDUSTRIES

2X

CROW'S NEST SOIL CONSERVATION DISTRICT

LOCALITY PLAN

Map 1.

1.

2.

3.

4.

5.

INTRODUCTION

CLIMATE

GEOLOGY

T ABLE OF CONTENTS

Part I - The Land Resources

THE LAND RESOURCE AREAS AND AGRICULTURAL MANAGEMENT UNITS

4. 1 Land Resource Areas

4.2 Agricultural Management Units

4. 2.1 4.2.2 4.2.3 4.2.4 4.2.5 4.2.6 4.2.7 4.2.8

Introduction Marburgs Land Resource Area Metamorphics Land Resource Area Granites Land Resource Area Basalt West Land Resource Area Basalt East Land Resource Area Basaltic Red Soils Land Resource Area Alluvium Land Resource Area

LAND USE AND LAND DEGRADATION

5.1 Existing Land Use

5.2 Land Degradation

Part II - Land Management

PAGE NO.

1.1

2. 1

3. 1

4. 1

4. 1

4. 1

4. 1 4.4 4.6 4.7 4.8 4.9 4.10 4.12

s. 1

s. 1

5.2

6. LIMITATIONS AND MANAGEMENT PRACTICES FOR AGRICULTURAL PRODUCTION

6.1 Introduction

6.2 Grain and Fodder Crops

6.3 Horticultural Crops

6. 3. 1 6.3.2

6.4 Pastures

6. 4. 1 6.4.2 6.4.3

Sma 11 Crops Tree and Vine Crops

Native Pastures Improved Pastures Pasture Management

6. 1

6. 1

6.6

6.6 6.6

6.7

6.7 6.7 6. 11

7.

8.

9.

ii

SPECIFICATIONS FOR RUNDFF CONTROL STRUCTURES

7. 1 7.2 7.3 7.4 7.5

7.6 7-7 7.8 7.9 7.1 0 7. 1 1

Introduction Runoff Estimation The Runoff Control Structures Specifications for Contour Banks Specifications for Modified Contour Banks/

Beds for Small Crops Specifications for Diversion Banks Specifications for Pondage Banks Specifications for Spreader Channels Specifications for Waterways Specifications for Grass Strips Specifications for Pasture Furrows

AGRONOMIC PRACTICES FOR EROSION CONTROL

8.1 Introduction 8.2 Grain and Fodder Crops 8.3 Horticultural Crops 8.4 Pastures

CONSERVATION MANAGEMENT SYSTEMS

9.1 Introduction 9.2 Grain and Fodder Crops 9.3 Horticultural Crops

9.4

9.3. 1 9.3.2

Pastures

Small Crops Tree and Vine Crops

10. SPECIFICATIONS FOR SPECIAL PURPOSE LAND US E

PAGE NO.

7. 1

7. 1 7. 1 7.4 7.5

7. 15 7.22 7.26 7.27 7.28 7-39 7.40

8. 1

8. 1 8. 1 8.3 8.3

9. 1

9. 1 9. 1 9.5

9.5 9.5

9.5

1 0. 1

1 0. 1 1 0.2 1 0.3

Specifications Specifications Specifications

for Subdivision and Farm Amalgamation for Rehabilitation of Top Soil Quarries for Reclamation of Severely Eroded Land

1 0. 1 1 '). 3 10.3

11. SUMMARY OF THE MANAGEf�ENT PRACTICES FOR THE M1Us

1 1 . 1 1 1 . 2 1 1 .3 1 1 .4 1 1 . 5

Marburgs, Metamorphics and Granites Land Resource Basalt West Land Resource Area Basalt East Land Resource Area Basaltic Red Soils Land Resource Area Alluvium Land Resource Area

BIBLIOGRAPHY

AP PENDICES

1 1 . 1

Areas1 1 . 2 1 1 • 14 11 . 17 11 . 22 1 1 . 30

12. 1

Appendix 1

Appendix I I

Appendix Ill

Appendix IV

Appendix V

Appendix V I

Appendix V I I

Appendix V I I I

Appendix IX

Appendix X

Appendix X I

Ai)pendix X I I

Appendix X I I I

Appendix X IV

Appendix XV

I ,

iii

APPENDICES

Detailed Soils' Information for the AMUs of the Basalt East, Basaltic �ed Soils and Alluvium LRAs -by S.E. Macnish

Soil A�alytical Data for Representative Profiles of the Basalt East,, Basaltic Red Soils and Alluvium L RAs -by S.E. Macnish

Land Capability Classification for Agriculture.

Determination of Rainfall Intensity for Use in the Rational Formula.

Peak Runoff from the Inter Bank Area for a Runoff Coefficient of 0.5 for the 1:10 design frequency.

Design Depth of Flow for Narrow Base Contour Banks.

Permissible Channel Gradient and Design Depth of Flow for the Various Types of Modified Contour Banks/Beds for Small Crop areas.

Furrow Velocities for a Range of Furrow Gradients in Small Crop Row Furrows.

Design Depth of Flow and Channel Capacity for Di,version Banks with a bottom Width of 3m.

Bottom Width and Design Depth of Flow for \Jaterways with a Bottom Width Less than 30 m for Grain and Grazing areas.

Bottom Width and Depth of Flow for Waterways with a Bottom Width Greater than 30 m for Grain and Grazing areas.

Design Depth of Flow for Waterways for Small Crop Areas .

Botanical Name of the Common Plant Species Listed in this Publication.

Potential of the Major Pasture Species for the Grow's Nest District.

Research and Monitoring Projects in the Grow's Nest District (January 1982) .

iv

ACKNOWLEDGEMENTS

I. Officers contributing major sections:

(i) Mr. S.E. Macnish -Provision of AMUs, soil profile descriptions and soil analytical data for the Basalt East, Basaltic Red Soils and Alluvium Land Resource Areas.

Section 4.2.6 and 4.2.7 and Appendices I and I I.

I I. Officers providing technical advice and editorial assistance:

(i) Mr. J.K. Cull -information on crop and pasture management.

(i i) Dr. W.J. Scattini -information on suitable pasture species.

(iii) Mr. G .W . Lubach - information on horticultural crop management.

(iv) Mr. A.W. Plasto -stocking rates for the AMUs.

(v) Dr. P.N. Truong -information on waterway species and maintenance.

(vi) Mr. N.M. Dawson, Mr. B.E. Vandersee and Mr. R.M . Stephens for helpful criticism and editing of the manuscript for this the first Land Management Field Manual.

I- 1

1, INTRODUCTION

Farm planning for optimum production with m1n1murn degradation to the land resource requires adequate definition of specifications for production and erosion control management. These specifications should be related to a suitable soils base that is both relevant to the area of concern and easily used by the farm planner. Such information should be recorded in an easily interpreted and readily useable format and should be reviewed and updated on a regular basis.

Information in this format is required for the Grow's Nest district located in the eastern Darling Downs of Queensland (Map 1).

This Grow's Nest field manual is the first in a series of manuals which will compile the land management practices for the major cropping areas of the State. The programme was commenced in its present form in late 1979 and has as its objectives:

(i) To provide a resource base for farm planning purposes by defining the major agricultural management units (AMUs) for each District;

(ii) To provide specifications for soil conservation measures, agronomic practices and conservation management systems;

(iii) To document this material in Land Management Field Manuals; and

(iv) To continually review and update the resource base and management specifications.

The programme currently involves co-operation between Soil Conservation, Agriculture and Development Planning Branches of the Department of Primary Industries and where applicable other agricultural organisations.

The end product of the programme will be a series of land management field manuals such as this for use by Departmental officers who are aware of the constraints of the manual.

This manual identifies (Map 3) and describes the land resource areas for the Crew's Nest district, and collates all available information on the soil resources together with their current management recommendations. The material contained in this field manual will be continually reviewed and updated as better information becomes available.

2-1

2. CLI�1ATE

Detailed climatic data are presented by Cull (1972) .

The approximate isohyets which were determined from Meteorological Bureau and farmer data are shown in Map 2. Mean annual rainfall varies from 650 mm at Meringandan to 1 200 mm at Ravensbourne.

The rainfall is summer dominant. Mean monthly rainfall for selected centres are shown in Map 2.

Mean monthly maximum and minimum temperatures for Toowoomba are shown in Map 2. On average, temperatures exceed 32

° C

in only 10 days of the year. Higher temperatures are expected east and west of the Great Divide. The first frost usually occurs at the beginning of May and the last frost in mid September.

Estimated tank evaporation exceeds average annual rainfall in all months of the year with peak evaporation occurring during December and January.

The district has been subdivided into climatic zones on the basis of mean annual rainfall and mean maximum temperature for January (Map 2) . The mean annual rainfall and mean maximum January temperature for the climatic zones are shown in Map 2. Agricultural management recommendations in Part II are based on tbese climatic zones.

Erosion Index (EI30

) data - both annual and monthly distribution - are presented by Rosenthal and White (1980) . Annual values for the district vary from 200 to 250 depending on location. Monthly distribution for the district is presented in Figure 2.1. The high erosivity rains during the summer months (Figure 2.1) are a limitation to cropping on the highly erodible soils in the district.

·�·r-------------------------------------------------�

100

90

80

70.

X 60 �

"" .: c 0

·;,;; e 50

UJ

o; � c c <(

40 0

/ "'

30 I I

20 I

10 I 0 I

Jan Feb Mar

.

./

_.. v ....

� ..--

_.

....------.....-

......

v

Apr May June July Aug Sept Oct

Figure 2.1 Erosion Index Distribution Curve for the Crow's Nest District

(After Rosenthal and White, 1980)

/

v

Nov

I I

Dec

N '

N

27"30'

151"45' 152"00' 152"15'

QUEENSLAND


EASTERN DARLING DOWNS REGION


CLIMATE AND CLIMATIC ZONES

5 0

�-.....

by J. Bierenbroodspot

SCALE 1:300 000

10

Drawn by S. Wallace

REFERENCE

Annual rainfall isohyet (mm)

15 km

B Climatic zone number (see below for description)

CLIMATIC ZONE AVERAGE ANNUAL AVERAGE MAX. TEMP. RAINFALL (mm) JANUARY ("C)

A1 750-950 <28

A2 >950 <28

B 750-950 28-32

c <750 28-32

BASE MAP supplied by thE! Royal Australian Survey Corps.

COMPILED by J. Bierenbroodspot, Soil Conservation Branch, Division of Land

Utilisation, Department of Primary Industries, Toowoomba.

27o30PREPARED by the Drafting Branch, Division of Land Utilisation, Department

of Primary Industries, Brisbane.

PRINTED by the Government Printing Office, Brisbane, 1981.

Map2.

3-1

3. GEOLOGY

The geology of the area has been mapped by Cranfield et al. (1976) and by Murphy et al. (1976). The geological units of these authors which give rise to similar soils have been grouped into composite geological units - see Table 3.1. The composite geological units form the basis for the land resource areas.

The geological history of the area is discussed by Mullins (1978) .

TABLE 3.1

COMPOSITE GEOLOGICAL UNIT

Metamorphics

Granites

Marburg Formation (predominantly coarse grained sediments)

Basalts

Lateritized Basalts

Alluvium

COMPOSITE GEOLOGICAL UNITS OF THE

CROW'S NEST VISTRICT

GEOLOGICAL UNITS OF CRANFIELD ET AL. (1976) AND MURPHY

ET AL. (1976)

Sugarloaf Metamorphics Maronghi Creek Beds

Cressbrook Creek Group

Woolshed Mountain Granodiorite Eskdale Granodiorite Crow's Nest Granite Djuan Tonalite Undifferentiated Intrusions Taromeo Tonalite

Tarong Beds Woogaroo Sub Group Marburg Formation

Main Range Volcanics

Lateritized Main Range Volcanics

Alluvium

MAPPING SYMBOL

Pzs Pzm

( Pch ( Peg ( Pc

Puo or Pgw P-Rge P-Rgc P-Rgt P-Rg P-Rt

Rt or Rut R-Jo or R-Jw Jm

Tm Tmc

Czb

4-1

4. THE LAND RESOURCE AREAS AND

AGRICULTURAL MANAGEMENT UNITS

4. 1 LAND RESOURCE AREAS

A land resource area (LRA) consists of a group of related soils developed on a common geology and in most cases having a similar vegetation community. Seven LRAs have been delineated:

(i) (ii) (iii) (iv) (v) (vi) (vii)

Marburgs Metamorphics Granites Basalt - West Basalt - East Basaltic Red Soils Alluvium

The major occurrences of the LRAs were mapped and are presented in Map 3 at a scale of 1:250 000. A key to the LRAs based on surface soil characteristics, landform, parent material and vegetation is presented in Figure 4. 1. The distinguishing features of each LRA are summarised in Table 4. 1.

4.2 AGRICULTURAL MANAGEMENT UNITS (AMUs)

4.2. 1 Introduction

An agricultural management unit is a group of soil series/ soil phases with similar agricultural and soil conservation management requirements.

The identification of an agricultural management unit in the field requires:

(a) The identification of the Land Resource Area. The use of the key in Figure 4. 1 will aid identification of the LRA. The LRA map (Map 3) can be used as a guide to identification.

(b) The identification of the soil series/phase and thus the AMU within each LRA. Soil profile descriptions and photographs in association with the soil keys (Appendix I and Mullins 1978) will provide sufficient information for the identification of the AMUs.

A summarised profile description together with a photograph of the soil profile are provided for the Basalt East and Basaltic Red Soils LRAs. Detailed soil profile descriptions of the AMUs in these LRAs are provided in Appendix I. Soil profile descriptions and soil profile photographs of the soils of the other LRAs are presented by Mullins (1978).

N I

...

Soils

FIGURE 4. 1 KEY TO THE LANV RESOURCE AREAS (LRAI) OF THE CROW'S NEST VISTRICT

Plains and Valley Bottoms A lluvium LRA

Slopes and

Hilltops

Absence of sand and sandstone gravel.

Presence of sand and sandstone gravel. The surface A horizon is clay loam or coarser.

Predominantly black earths and li thosols ----i developed on basalt.

Predominantly krasnozems developed on laterite and tuffaceous material. Minor colluvial black earths occur in association.

Marburg Formation type

..__ __

Strongly structured, self mulching soils, developed on basalt; predominantly on the western slopes of the main range; predominantly open forest to woodland of mountain coolibah or open forest of mountain coolibah and narrow-leaved ironbark with a scrub understory. �---- Basalt

Weak, finely structured surface soils developed on basalt; predominantly on plateau remnants and dissected hills east of the

West LRA

main range; predominantly open forest of narrow -leaved ironbark or closed forest of softwood scrub species. Basalt

East LRA

Basaltic Red Soils LRA

parent material - - -- ---------- - - - --- Marburgs LRA

Metamorphic parent material

Granite parent material

- ----------- - - ------ Metamorphics LRA

-- - - ---------- - - - -- - Granites LRA

152"15'

27'00'

27'15'

27'30'

151'45' 152'00' 152'15'

QUEENSLAND 27"00'


EASTERN DARLING DOWNS REGION


27'15'

LAND RESOURCE AREAS

by J. Bierenbroodspot

SCALE 1:300 000

Drawn by S. Wallace

REFERENCE

MET AMORPHICS

2 GRANITES

3 MARBURGS- Predominantly coarse grained sediments (includes Tarong Beds, Woogaroo Sub-Group and Marburg Formation.)

4 BASALTS-WEST

5 BASALTS- EAST

6 BASAL TIC RED SOILS

7 ALLUVIUM

BASE MAP supplied by the Royal Australian Survey Corps.

COMPILED by J. Bierenbroodspot, Soil Conservation Branch, Division of Land

Utilisation, Department of Primary Industries, Toowoomba.

27•30• PREPARED by the Drafting Branch, Division of Land Utilisation, Department

of Primary Industries, Brisbane.

PRINTED by the Government Printing Office, Brisbane, 1981.

Map3.

4-3

Table4.1 DISTINGUISHING FEATURES OF THE LAND RESOURCE AREAS OF THE CROW'SNEST DISTRICT

Features Metamorphics Granites

Parent Metamorphics Granites and granodiorites. Material

Physiogr-aphy Steep ro mountainous.

Undulating to hilly.

Soils

SIO!face Soil

Texture

Vegeta-tion

Other Soil Features

Shallow, stony sands and loams (lithosols) and hard setting loams and clay loams overlying yellowish grey, clay sub soils (solodi;;;ed solonet:z/ solodics) and reddish brown clay loams overlying red and brown, clay sub soils (redbrown earths

Shallow to moderately deep sands and learns (li thosols and siliceous sands) and grey sands to loams overlying red and brown clay subsoils (red brown earths, yellow earths and solodized solonetz/ solod:ics).

and yellow earths)

Clay loam or coarser.

Open forest to woodland of narrow leaved ironbark and grey gum.


Open forest to woodland of grey gum and narrow leaved ironbark.

Sand is present Sand is present on the soil on the soil surface and surface and throughout throughout the the soltllll. solum.

Marburgs Basalt West

Coarse grained Basalt sedime nts of the Marburg Formation, Woogaroo Sub Group and Tarong 13eds.

Undulating to Undulating to hilly. steep.

1Iard setting loams to clay loams overlying yellowish grey, clay sub soils (solOdized solonetz/ c;olodics). Deep sands (siliceous sands), reddish brown clay loams overlying red .9.Dd brown clays (red-brown earfrs and yellow eart� and shallow, stony sands and loams (lithosols).


Layered open forest to ;;hrubby woodland of narrow leaved ironbark, gum topped box, bull oak (west of Great Divide only) and wattles. Communities of Queensland blue gum, silver leaved ironbark, white stringy bark and grey gum occur.

Moderately dee;:> to deep, self mulching, dark, cracking clays (black earths) with fine to medium surface structure. Shallow, stony soils (1Hhosols) occur on �he upper stores and hill tops.

Predominantly heavy clays. Some clay loams

Open forest to woodland of mountain coolibah, or open fares t of mountain coolibah and ironbark ,;ith an underston> of scrub species.

Sand is present on Peds with smooth, the soil surface shiny faces and throughout the occur throughout soltllll. the solum.

Basalt East Basaltic Red Soils Alluvium

Basalt Lateritized basalts Mixed alluvia derived and tuff. from a range of other

parent materials in the District.

Steep hilly to IDOuntainous with short steep slopes and narrow valleys,

Plateaux and short Flat to gently sloping steep slopes. vall<>Y floors.

1ioderately deep to lloderat.,ly deep to deep, dark, crackillg deep, gradational, clays (black e3rths) red soils with weak to strong: (krasnozems) with very fine to fine a friable surface. surface structure. Surface structure Shallow stony soils is IUOderate, medium (lithosols) occur granular to on the upper slopes structureless. and hill tops. Some dark colluvial

soils occur on lower slopes and in the depression lines.

Predominantly heavy clays.

Open forest to woodland of narrow leaved ironbark or closed forest of softwood scrub species.

Predominantly light to medium clays and clay loarns.

Either a layered open forest of white stringy bark, Sydney blue gum, tallowwood and red bloodwood with an understorey of wattles and black she oak or a closed forest of Sydney blue gum and softwood scrub species or a closed forest of rainforest species.

Deep, dark,self mulching, cracking clays (black earths) to hard setting te:Kture contrast soils (red-brown earths, soloclized solonetz/ soloOics).

Varies from heavy clay to sandy loam.

Grassy open woodland of Queensland blue gum, or rough barked apple or silver leaved ironbark. Some grassland.

Peds with smooth, shiny faces occur throughout the sol urn.

Earthy, rough faced, Both deep, uniform clays crumb structured peds and hardsetting in the A horizon loamy duplex soils. overlying a B horizon Not an extensive with smooth, shiny soil group. faced peds.

4-4

4.2.2 Marburgs Land Resource Area

The Agricultural Management Units (AMUs) of the Marburgs LRA are separated on the four properties outlined in Table 4. 2. The AMUs are summarised according to those properties in Table 4.3. Abbreviated soil profile descriptions together with soil profile photographs for the AMUs in this LRA are presented by Vandersee in Mullins (1978). Detailed soil profile descriptions are presented by Vandersee in Vandersee and Mullins (1977).

The most commonly occurring AMUs in the district are:

FSI (TC) MF* CSI (TC) MF FSI (U) MF CSI (U) MF CMI (TC) MF CDI (TC) MF FMH (TC) MF CSH (TC) MF CMH (TC) MF CS-MP (TC) MS* FS-MP (TC) MS FS-MP (TC) MF

(*MF = Marburgs Forest; *MS = Marburgs Scrub)

Techniques for field identification of the permeability of sub soils of texture contrast soils are presented in Vandersee (1977) and Mullins (1977).

TABLE 4.2 CATEGORIES OF FOUR SOIL PROPERTIES ANV

ASSOCIATEV SYMBOLS USEV TO IVENTIFY THE SOIL

UNITS OF THE MARBURGS LRA

SOIL PROPERTY

Texture of the A horizon

Depth of the A horizon

Permeability of the B horizon

Texture profile type

CATEGORY

Fine (loam to clay loam) Coarse (coarser than loam)

Shallow ( < 15 em) Moderate (15 - 30 em) Deep ( > 30 m)

Impermeable Partially Permeable Permeable

Texture Contrast Gradational Uni.form

SYMBOL

F

c

s M D

I H p

TC G u

4-5

TABLE 4.3 AGRICULTURAL MANAGEMENT UNITS

OF THE MARBURGS LRA

A HORIZON PERMEABILITY OF TEX11JRE

TEXTURE DEPTH (CM) THE B HORIZON PROFILE TYPE

< 15 Impermeable Texture contrast

Uniform

Partially Permeable Texture contrast

Loam Partially Permeable Texture contrast

to 15 - 30 Impermeable Texture contrast

Clay Uniform

Loam > 30 Impermeable Uniform

Permeable Uniform

All Depths Permeable Texture contrast

Gradational

< 15 Impermeable Texture contrast

Uniform

Partially Permeable Texture contrast

Coarser 15 - 30 Partially Permeable Texture contrast

than Impermeable Texture contrast

Loam Uniform

>30 Impermeable Texture contrast

Uniform

All Depths Permeable Texture contrast

Gradational

AMU SYMBOL

FSI (TC)

FSI (U)

FSH (TC)

FMH (TC)

FMI (TC)

FMI (U)

FDI (U)

FDP (U)

FS-MP (TC)

FS-MP (G)

CSI (TC)

CSI (U)

CSH (TC)

CMH (TC)

CMI (TC)

CMI (U)

CDI (TC)

CDI (U)

CS-MP (TC)

CS-MP (G)

NOTE: (i) Profiles with shallow and moderately deep surface A horizons have been combined as one unit (FS-MP and CS-MP) .

(ii) FS-MP (TC) - The texture of the surface A horizon is predominantly a clay loam. Light clays do occur.

(iii) FDP (U) only occurs in the Alluvium LRA.

(iv) Not all soils listed in Table 4.3 occur in the Craw's Nest District.

4-6

4.2.3 Metamorphics Land Resource Area

The AMU classification for the Marburgs LRA has been used to classify soils in the Metamorphics LRA. As for the Marburgs, AMUs have been separated on the four properties outlined in Table 4.2 and the AMUs are summarised according to these properties in Table 4.3. Abbreviated soil profile descriptions together with a soil profile photograph for the AMUs in this LRA are presented by Vandersee in Mullins (1978). Detailed soil profile descriptions are presented by Vandersee in Vandersee and Mullins (1977).

AMUs recorded in the Metamorphics LRA include:

(i) (ii) (iii) (iv)

CSI (U) - M CSI (TC) - M CS-MP (TC) - M FSP (G) - M

(M = Metamorphics) .

4-7

4.2.4 Granites Land Resource Area

The AMU classification for the Marburgs LRA has been used to classify soils in the Granites LRA. As for the Marburgs, AMUs have been separated on the four properties listed in Table 4. 2 and the AMUs are summarised according to these properties in Table 4.3. Abbreviated soil profile descriptions together with a soil profile photograph for the AMUs in this LPJl are presented by Vandersee and Mullins ( 1978). Detailed soil profile descriptions are presented by Vandersee in Vandersee and Mullins (1977).

AMUs recorded in the Granites LRA include:

(i) (ii) (iii) (iv)

CSI (U) - Gr CMI (U) - Gr CS-MP (TC) - Gr COP (TC) - Gr*

(Gr � Granites)

* This unit does not occur in the Marburgs LRA and is not listed in Table 4.3.

------ .--- .

4-8

4.2.5 Basalt West Land Resource Area

Two AMUs occur in this LRA in the Crow's Nest District:

(i) Kenmuir (ii) Purrawunda

Abbreviated soil profile descriptions together with a soil profile photograph for the AMUs are presented by Cummins and Macnish in Mullins (1978). Detailed soil profile descriptions are presented by Thompson and Beckmann ( 1959).

4-9

4.2.6. Basalt East Land Resource Area

Five AMUs occur in this LRA:

(i) BSs (ii) BSd (iii) BFs (i v) BFd (v) BFwd

(B = Basalt; S = Scrub; F = Forest; s = shallow soil profile; d = deep soil profile; w = weakly structured surface soil)

An abbreviated soil profile description, a soil profile photograph and the distinguishing features for each AMU are presented in this section. Detailed soil profile descriptions and a soil key for the LRA are presented in Appendix I.

Distinguishing Features of the AMUs.

BSd Basalt scrub deep

(i) (ii) (iii) (iv)

Brownish black, medium to heavy, cracking clay. Weak to moderate fine surface structure. Moderately deep to deep soil. Occurs mainly on lower slopes.

BSs Basalt scrub shallow

(i) (ii) (iii) (iv)

Brownish black, clay loam to light clay. Weak, fine surface structure. Shallow stony or gravelly soil. Occurs mainly on ridges and upper slopes.

BFs Basalt forest shallow

(i) (ii) (iii) (iv)

Black or brownish black, clay loam to medium clay. Weak, medium granular structure. Shallow stony or gravelly soil. Occurs mainly on ridges and upper slopes.

BFd Basalt forest deep

(i) (ii) (iii) (iv)

Brownish black, medium to heavy, cracking clay. Strong granular structure. Moderately deep to deep soil. Occurs in mid and lower slope positions.

BFwd Basalt forest, weak structure, deep

(i)

(ii) (iii) (iv)

Brownish black, light clay; weakly cracking in virgin condition, but cracking more pronounced when cultivated. Structureless to weak, fine crumb surface. Moderately deep to deep soil. Occurs in mid and lower slope positions.

4-10

4.2.7 Basaltic Red Soils Land Resource Area

Seven AMUs occur in this LRA:

( i) Cabarlah (ii) Pechey (iii) Palmtree (i v) Geham (v) Ravens bourne (vi) Pinelands 1 and 2

(vii) Merritts

An abbreviated soil profile description, a soil profile photograph and the distinguishing features for each AMU are presented in this section. Detailed soil profile descriptions and a soil key for the LRA are presented in Appendix I.


Cabarlah

Geham

Pechey

( i)

(ii) (iii)

(i v)

(i ) (ii) (iii)

(i v)

Reddish brown loam to clay loam surface.

Weak fine crumb surface structure. Very shallow to shallow gravelly soil, with ironstone nodules. Occurs on ridges, upper slopes and on some plateau remnants.

Dark brown, light to medium clay surface. Weak granular surface structure. Small to moderate amounts of ironstone nodules and gravels in dark A horizon. Moderately deep soil but generally poor permeability below 60 em.

(v) Often associated with perched water table. (vi) Occurs in lower slopes and in broad valley floors

generally below Cabarlah AMU.

(i) (ii) (iii)

(i v)

Dark reddish brown, loam. Structureless, •snuffy' surface. Deep to very deep soil with some ironstone nodules and gravels Generally occurs on plateau and upper slopes.

Pinelands

Pinelands

Merritts

Palmtree

1

(i) (ii) (iii) (iv)

(v)

2

(i) (ii)

(iii)

(iv)

(i) (ii) (iii) (iv)

(i) (ii) (iii) (i v) (v)

Ravens bourne

(i) (ii) (iii)

(iv)

4-11

Dark reddish brown light clay. Moderate granular surface structure. Shallow to moderately deep soil overlying basalt. Moderate amounts of stone on surface and through the profile. Also lateritic gravels occur. Occurs on benches below Pinelands 2 AMU and is a sedentary Soil developed on basalt with colluvial additions from Pinelands 2 AMU.

Dull reddish brown, light clay. Structureless to weak surface but little organic accumulation. Deep, strongly acid profile; some lateritic gravels throughout. Generally occurs on ridges, plateaux and upper s'lopes above Pine lands 1 AMU.

Brownish black, medium, cracking clay. Moderate granular surface structure. Moderately deep soil. Generally occurs in broad shallow drainage depressions and lower slopes. This is a colluvial soil derived from basaltic and lateritic material. Often occurs below Pechey AMU.

Dark reddish brown, light clay. Very friable, fine granular surface. Moderately deep soil. Subsoil below 60 em has poor permeability. Occurs in most slope positions.

Dark reddish brown clay loam to light clay. Weak fine crumb surface structure. Deep to very deep soil. Increasing amounts of lateritic gravels with depth. Occurs in most slope positions, generally east of the Great Dividing Range.

4-12

4.2.8 AI luvium Land Resource Area

Four AMUs occur in the LRA.

(i) (ii) (iii) (iv)

Waco Als Alw Alh

(Al = Alluvium; s = st�ongly structured surface; w = weakly structured surface; h = hard setting surface. )

An abbreviated soil profile description for the Waco together with a soil profile photograph is presented by Cummins and Macnish in Mullins (1978) and a detailed soil profile description is presented by Thompson and Beckmann (1959). An abbreviated soil profile description and the distinguishing features for the other AMUs are presented in this section. Detailed soil profile descriptions are presented in Appendix I.


Als

(i) (ii) (iii) (i v)

Alw

(i) (ii)

(iii) (i v)

A lh

(i) (ii) (iii) (iv) (v)

Brownish gray, self -mulching, cracking heavy clay. Strong, fine blocky surface structure. Deep to very deep soil in valley floors. Derived from alluvia of predominantly basaltic origin.

Brownish black, cracking, medium to heavy clay. Weak, fine crumb surface structure; surface crusting may occur. Deep to very deep soil in valley floors. Developed from alluvia of predominantly basal tic and lateritic origin.

Brownish black, sandy clay loam surface. Hardsetting massive surface soil. Texture contrast profile. Deep to very deep soil in valley floors. Developed on predominantly sandstone alluvia with some basaltic influence.

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5-1

5. LAND USE AND LAND DEGRADATION

5.1 EXISTING LAND USE

Most farmers on the 137 000 ha of rural holdings rely on animal production for their main source of income - dairying, vealer production and cattle breeding and fattening. Only 5% (7 117 ha) of the total area is used for cultivation. The area used for cultivation in each Land Resource Area is indicated in Table 5.1. Of the total area of cultivation, 60 to 70% is used for fodder cropping and the remainder for grain cropping. There is now a tendency to discontinue grain growing on the steep, smaller areas in favour of returning the land to improved pasture. This trend should be encouraged.

In areas with an average annual rainfall of less than 800 mm,

winter grazing crops are used to improve dairy production and to a lesser extent for vealer production. Oats is the main fodder crop grown to provide quality feed in winter and spring. There is an increasing interest in the growing of Dolichos lab lab for autumn feeding. Because of the limited area of land suitable for cultivation, oats is often grown on land that because of the high erosion risk is unsuitable for continuous cultivation. With increasing rainfall, the growing of winter grazing crops becomes less important and in the Ravensbourne area with an average annual rainfall of 1 020 mm, farmers rely on a combination of temperate and tropical pastures to provide stock feed at all times of the year.

Of the 130 dairy farmers in the district, 115 supply milk to the Toowoomba and Quinalow factories on a variable percentage of market to manufactured milk. Farmers who supply market milk are more likely to use winter grazing crops than other dairy farmers or graziers to achieve maximum production in winter. In summer the ratio of higher priced market milk to manufactured milk is 3:7, but is reversed in winter. An increase in market milk production in the district is likely to cause an increase in the area used for winter fodder crops and an increase in the use of kikuyu and white clover in sui table areas.

Improve pastures, such as Rhodes grass, Setaria and lucerne provide feed of good quality for fattening cattle and few land use problems occur in these grazing areas providing sound management practices are adhered to.

Approximately 7 200 ha of State Forest and Timber Reserve occur in the District. Forestry is based on logging of stands of native timber including narrow-leaved ironbark, silky oak and hoop pine and plantations of exotic pines in the Pechey area.

Approximately 50 hectares are used for tree crops and small crops. This area is expanding, especially in the Ravensbourne area, for avocados, pecan nuts and kiwi fruit. If irrigation water becomes available an expansion of the horticultural industry could be expected, especially on the Basaltic Red Soils LRA.

5-2

Substantial subdivision of land into occurred in the Cabarlah and Toowoomba areas. farms have been subdivided into 12 ha farmlets Red Soils LRA which is good agricultural land.

1-5 ha hobby farms has In some cases larger mainly on the Basaltic

Perseverance and Cooby Creek Dams and the two National Parks (Craw's Nest Falls and Ravensbourne) provide for recreational land use. A third dam on Cressbrook Creek is currently under construction. Because of its physical attractions and proximity to Brisbane and Toowoomba there is a potential for expansion of recreational land use in the district. If not planned, some of this development could lead to soil erosion.

The quality of underground water varies from good in the Basaltic areas to poor in the Marburg Formation areas. Yields of underground water are low.

There is considerable scope for irrigation using small to medium sized earth dams. It is estimated that 15-20% of the upper catchments of the district have suitable sites for such earth dams with adequate catchment area for irrigation of either improved pastures or tree crops (with trickle irrigation) where soils are suitable.

Total soluble salt levels are high in some creeks in the Marburgs LRA. It is therefore desirable to check salinity levels of the water before constructing an earth dam.

Land use for the district is summarised in Table 5.1.

5.2 LAND DEGRADATION

The following forms of land degradation occur - water erosion (on cultivation and on pasture land), landslip, secondary soil salinity, woody weed regrowth and pasture degradation.

Water erosion occurs both as sheet and gully erosion in cropping and pasture land. Gully erosion mainly occurs on farms with a long history of cropping or in areas with dispersible subsoils. Sheet erosion associated with a long history of cropping has resulted in severe soil losses. It is not uncommon for a 1 metre drop to occur along a fence line. Badly eroded cultivated areas have been removed from cultivation.

The soil erosion situation for the LRAs is summarised in Table 5 .1.

The majority of land currently used for cultivation occurs on steep slopes (Table 5.2) and requires soil conservation measures to reduce soil loss to acceptable levels.

LAND RESOURCE AREA

Basalt West

Basalt East

Basaltic Red Soils

TABLE 5. 7 LANV USE ANV SOIL EROSION IN THE CROW'S NEST VISTRICT

LOCATION AND AREA (HA)

Meringandan (5 000)

Haden/Coalbank ( 14 000)

Highfields (7 000)

Hampton/ Craw's Nest (9 000)

AVERAGE ANNUAL RAINFALL (W-1) AND

CLIMATIC ZONE

650 - 800 I c

750 - 800 I B

900 I A 1

830 - 940 I A1

CURRENT LAND USE

Dairying and grazing on mostly very small farms ( < 40 ha). Many parttime landholders. Small area of cultivation -342 ha.

Dairying and grazing on small to medium sized farms (100 - 300 ha). 9ome graingrowing. Most farms have some cultivation, either on steep land slopes or the alluvial flats. Total area Of cultivation is 1 935 ha.

Dairying, piggeries, poultry, some horticulture on very small farms ( < 40 ha) . Major area of subdivision with many hobby farms . Total a�ea of cultivation is 914 ha.

Dairying and grazing on small to me·dium sized properties. Some cultivation on fairly steep slopes. Total area of cultivation is 602 ha. Forestry plantations of exotic pines.

SEVERITY OF SOIL EROSION

Severe sheet and gully erosion occurs on 302 ha of the cultivated area. Minor erosion may occur on the remaining cultivated land.

Severe sheet erosion occurs on 1 613 ha of the cultivated area, Some gul)y erosion also occurs. Minor erosion may occur on the remaining cultivated land.

Light to moderate sheet erosion occurs on all cultivated areas.

Moderate erosion occurs on all cultivated areas. Areas of severe erosion have been abandoned.

LAND RESOURCE AREA

Basal tic Red Soils

Marburgs


Hampton -Ravens bourne (8 000)

Blackbutt Range (5 000)

Meringandan (9 000)

Coalbank -Crow' s Nest ( 18 000)

AVERAGE ANNUAL RAINFALL (MM) AND

CLIMATIC ZONE

900 - 1 200 I A2

1 ooo I A2

760 I c

800 I B

TABLE 5 .7 {CONTINUEV)

CURRENT LAND USE

Dairying and grazing of pasture. Only 260 ha of permanent cultivation. Some areas of temporary cultivation for the establishment of improved pastures. Small areas of avocados.

Grazing and State Forest. Grain and peanut cropping on 240 ha.

Dairying and grazing on very small farms ( < 40 ha) . Some hobby and part-time farmers. Limited area of cultivation - 423 ha. Forest reserve to protect Cooby Creek Dam.

Dairying and grazing on small to medium sized farms (100 - 300 ha). Grazing on larger properties. About half the total number of farms have some cultivation. Total area of cultivation -2 2 35 ha. Some graingrowing.


All cultivation has slight soil erosion.

Moderate sheet erosion on all cultivated areas. Some areas of lands lip.

Serious sheet and gully erosion of cultivated areas.

Severe sheet and gully erosion of cultivated areas. Some minor erosion on grazing land. Moderate erosion is occurring on areas of abandoned cultivation and in gully lines of soils with dispersible sub soils.

��

LAND RESOURCE AREA

Granites, Metamorphics and Marburgs

Metamorphics and Granites

Alluvium


Murphy's Creek and Ravens bourne (15 000)

East of New England Highway between Hampton and Coalbank (7 300)

Occurs as small areas in association with other Land Resource Areas.

AVERAGE ANNUAL RAINFALL (MM) AND

CLIMATIC ZONE

900 - 1 200 I A2

800 - 900 I B

TABLE 5.1 (CONTINUED)

CURRENT LAND USE

Areas of extensive grazing and State Forest. Some hobby farms in the Murphys Creek area. Limited area of cultivation - 69 ha.

Grazing on large holdings ( > 300 ha). Metamorphics largely undeveloped because of steep slopes. Little cultivation - 96 ha.

Cultivation, for the growing of grain and grazing crops. Improved pastures.


Moderate erosion occurs on cultivated areas. Some areas of landslip. Some pasture areas are eroded especially gully lines on dispersible subsoils.

Moderate erosion occurs on cultivated areas. Some pasture areas are eroded, especially gully lines on dispersible sub" soils.

No erosive flooding. Some areas require diversion banks and/or waterways to divert runoff from higher areas.

<.n '

<.n

TABLE 5 .2

LAND SLOPE CATEGORY (%)

5-6

PERCENTAGE OF TOTAL CULTIVATED LANV

ON THE LANV SLOPE CATEGORIES

% OF TOTAL CULTIVATED AREA

Valley floors 0 - 1 Slopes 1 - 5

10 14 41 35

Slopes 5 - 8 Slopes > 8

Roadside erosion can be a problem associated with cross road drainage structures. Erosion of t able drains is not common. Erosion of disused quarries varies considerably. Most top soil quarries seem to stabilise with woody regrowth and native p asture after an initial period of instability. Serious gully erosion occurs in quarries where the sandy top soil of texture contrast soils has been removed. Such a situation exists near Cooby Creek Dam.

Landslip is confined to the vicinity of the eastern excarpment of the Great Dividing Range and to the Blackbutt Range. Landslip generally occurs in prone areas after a 3 to 4 hour period of intense rain during a 2 to 3 day rainfall event. Areas that are particularly prone to landslip include:

(i) Areas where the parent material is underlain by impermeable mudstones (e.g. the Marburg Formation), forming a slip face;

(ii) Areas where the basalts (mostly lateritised) can

slide along the cont act zone with the underlying sedimentary or metamorphic rocks (Basaltic Red Soils LRA);

(iii)

(iv)

At gully heads where the soil is most likely to be supersaturated; and

Where spring outbreaks occur (Holmes, 1981) .

Mass movement 1s generally restricted to slopes > 10% but the lithology and structure of the underlying geology can cause landslip in areas with slopes < 10%.

Secondary s alinity has been observed in the 11arburgs LRA but is not a serious problem at this stage.

The district has been used for intensive grazing since settlement in 1850. Due to overgrazing, the better grasses have often been replaced by edible but unproductive grasses like wire grass, love grass, barbed wire grass and ratstail grass.

S-7

Lantana is the main woody weed of the district and is most common on the better soils in climatic zones A and B. Heavy infestations occur in the less accessible areas on steep land slopes. Bulldozing and cultivation prior to establishing improved pastures are generally used to control heavy infestations. However, these practices may result in serious soil erosion.

Following clearing of native vegetation, wattles can be a problem on those soils with impermeable subsoils of the Marburgs LRA. Bracken fern and blady grass infest most AMUs in climatic zones Al and A2. Cropping or ploughing prior to sowing improved pasture will normally give temporary control of these two species. Carpet grass or mat grass has recently invaded some pastures on the Basaltic Red Soils LRA near Ravensbourne, and veined verbena is causing some problems on the Basaltic Red Soils LRA between Toowoomba and Geham. Other weeds such as wild turnip and barnyard millet are often associated with fodder crop cultivation.

' , .-------------------------�-----

6-1

6. MANAGEMENT LIMITATIONS AND PRACTICES

FOR AGRICULTURAL PRODUCTION

6.1 INTRODUCTION

The suitability of the AMUs for crop and pasture production and the management requirements for optimum production are defined. The management limitations for agricultural management are listed in Chapter 11 for each AMU. Additional detail on the limitations for the AMUs is available in publications on the "Key Area Studies" for the Land Resource Areas (e.g. Vandersee in Vandersee and Mullins, 1977).

The presence and degree of limitation of the 14 limiting factors of the Land Capability Classification for Agriculture of Rosser et al. (1974) are presented for each AMU in Table 6.1.

6.2 GRAIN AND FODDER CROPS

The major crops commonly grown are grain barley, grazing oats and fodder sorghum.

The suitability of the soils for grain and fodder cropping is presented in Table 6. 2.

The shallow stony soils of the Basalt East, Basalt West and Basaltic Red Soils LRAs are unsuitable for cropping due to their shallow soil depth, very low available soil water capacity and the large amounts of stone throughout the profile.

Within the Marburgs, Granites and Metamorphics LRAs, those soils with shallow A horizons over impermeable B horizons are unsuitable for all types of cropping due to the low ·plant available water capacity and low nutrient status. In addition, cultivation of these soils in this climatic environment will lead to exposure of the impermeable, dispersible and highly erodible B horizon. Those soils with a deep surface A horizon over an impermeable B horizon can be used for winter fodder cropping. Those soils with a moderately deep surface A horizon over an impermeable B horizon Cffi\ with careful management be used for winter fodder cropping.

Most of the arable soils of the Marburgs and Metamorphics LRAs will set hard under continuous cultivation or after heavy rain. The soils should be worked when they are in a moist condition to avoid the formation of large clods. On the arable soils of the Marburgs and Metamorphics LRAs, the soils of the Basaltic Red Soils LRA and the weakly structured soils of the Basalts East LRA, tined implements should be used in preference to disc implements to reduce pulverisation of the fragile surface structure.

-----------------------··--� .. ------

6-2

TABLE 6.1 LANV CAPABILITY CLASSIFICATION

LRA/AMU

Basalt West

Kenmuir Purrawunda

Basalt East

BS s BF s BS d BF d BF w d

Basaltic Red Soils

Cabarlah Pechey Palmtree Geham Ravens bourne Pinelands 1 and 2 Merritts

FOR AGRICULTURE FOR EACH AMU

CLASS

V I I I- IV

V I-VII V I-VII I II-VI I I I-VI I I I-V I

V-VI I I I-IV III-VI III-IV IV-VI IV-VI I I I-VI

Marburgs/Granites/Metamorphics

CSI (TC)MF FS I (TC)MF CSI (U)MF FSI (U)MF CMI(TC)MF CDI (TC)MF CSH (TC)MF CMH (TC)MF FMH (TC)MF CS-MP (TC)MS FS-MP (TC)MS FS-MP (TC)MF CSI (U) Gr CM I (U)Gr CS -MP (TC) Gr CDP (TC)Gr CSI (TC)M CSI (U)M CS-MP (TC)H FS-MP (G)M

Alluvium

Waco Al s Al w Al h

VI-V I I V I-VII VI-VII VI-V I I IV-VI I I I- IV IV IV IV I II-VI I I I-VI I I I-VI VI-VI I IV-VI I I I- IV I I I -IV VI-V I I V I I-V I I I IV-VI I I I-VI

I-I I I-II I I I II

LIMITATIONS AND SUBCLASS

e4-6 m3 d4-6 r 3-5 e2-4

e6 m3 d4-6 r4-5 t6-7 e6 m3 d4-6 r4-5 t6-7 e3-6 e3-6 e3-6 m2 p2 dl-2

e3-6 m4 n3 d4-6 r3-5 e2-4 m2 n2 p2 e3-6 m2 nl-2 e2-4 m2 n2 p2 e4-6 m2 nl-2 e4-6 m2 nl-2 e3-6 nl-2

e6d6m4n4k4p4s2-4 e6d6m4n4k4p4s2-4 e6d6m4n4 e6d6m4n4 e4-6 d4 m4 n4 s2-4 e3-4 m3 n3 e3-4 m2 n3 s2 e3-4 m2 n3 s2 e3-4 m2 n2 s2 p3 e3-6 m2 e3-6 m2 e3-6 m2 e6d6m4n4r4-5 t6-7 e4-6 m4 n3 t6 d4 e3-4 m3 n2 e3-4 m 3 n2 e6d6m4n4 t6-7 e6d6m4n4 t 7-8 e4-6 m2 n2 e3-6 m2 n2

el-2 el-2 el-2 p2 el-2 m2 n2 p2

s2-4 rS

r4-5

6-3

TABLE 6.Z SOIL SUITABILITY FOR VRYLANV GRAIN ANV

FOVVER CROPPING IN EACH CLIMATIC ZONE

LRAs AMUs

Basalt West, Basalt East. Kemnuir, BPs, BSs, ) Basal tic Red Soils Cabarlah )

Basalt West, Basalt East. All soils except ) Kenmuir, BPs, BSs. )

Alluviwn All Soils ) Basaltic Red Soils. All soils except )

Cabarlah. ) Marburgs, Granites, FS-MP (TC and G) ) Metamorphics FMH(TC) )

Marburgs, Granites, CSH(TC), Q.1H (TC), ) ) Metamorphics CS-MP(TC), CDI(TC),)

CDP(TC).

MarbD:rgs, Granites, Metamorphics.

Marburg5, Granites, Metamorphics.

s sui table

CMI(TC), CMI(U), FMI(TC).

CSI(TC), cs-r cuJ, FSI(TC), CSI(U).

ls � limited suitability ns not suitable

)

)

)

) )

* suited to wheat as well as barley

CROP TYPE

All crops

winter grain *

winter fodder sununer grain summer fodder

winter grain winter fodder summer grain swnmer fodder

winter fodder other crops

all crops

CLIMATIC ZONE A B c

ns ns ns

s s s s s s s s s s s s

s ls ls s s s s ls ls s s ls

ls ls ls ns ns ns

ns ns ns

6-4

The following agronomic management recommendations should be used more extensively:

(i)

(ii)

(iii)

(iv)

Fast growing crops with low water requirements such as millet and panicum crops could be used more extensively on soils with low to moderate levels of available soil water. These crops are not suited to the extremely hard setting soils.

Wheat as well as barley* could be grown on soils of the Basalt East, Basalt West and Alluvium LRAs. Wheat is more suited to thOse soils with a moderate to high nutrient status and plant available water capacity whereas barley can be grown on the poorer soils.

Winter fodder cropping is undertaken to alleviate winter feed shortages. However additional summer fodder cropping may be warranted to alleviate protein shortages in the autumn period.

Because of the low nitrogen status of the soils and the high cost of nitrogenous fertilizers, leguminous fodder crops should be used wherever possible. For example:

(a) Woolly pod vetch - similar water requirements to oats but produces less bulk.

(b) Dolichos lab-lab - similar water requirements to forage sorghum.

(c) Cow peas - lower water requirements than forage sorghum. Cow peas are therefore particularly suited to soils of the Basaltic Red Soils, Marburgs, Granites and Metamorphics LRAs.

(v) Undertake opportunity cropping. This practice has considerable potential on the arable soils of the Marburgs LRA. Crops will respond to small falls of rain on these soils.

(vi) A pasture phase should be included in all crop rotations where erosion cannot be adequately controlled with continuous cropping (see Chapter 9).

Generalised fertilizer requirements for six broad groups of AMUs for dryland cropping are presented in Table 6.3.

In groups 2 and 3, phosphorus levels are either marginal or vary considerably. In groups 5 and 6,phosphorus levels can vary from very low to low. In group 6, potassium levels can vary considerably, but generally no response to potassium occurs because of other limiting factors (N, P and moisture). Those soils with loam to clay loam surfaces generally have adequate levels of potassium, while those with sandy surfaces have very low levels of potassium.

* Until recently barley varieties have out yielded wheat. With new wheat varieties, this does not seem to be the case now.

��

•

TABLE 6.3 FERTILIZER RECOMMENDATIONS FOR GRAIN AND FODDER CROPS ON THE AMUI

GROUP

1

2

3

4

5

6

LRA

Basalt West Alluvium

Basalt East Alluvium

Basaltic Red Soils

Basalt East Marburgs, Granites Metamorphics Alluvium

Mar burgs

Basaltic Red Soils

Marburgs, Granites, Metamorphics.

Purrawunda Waco Als

BSd, BFd Alw

AMUs

Palmtree, Pinelands, Ravens bourne B F wd FS-MP (TC), FS-MP (G)

Al h

FMH (TC)

Pechey, Geham, Merritts

CSH (TC), CMH(TC) CS-MP (TC), CDI (TC), CDI (U), CDP (TC)

PHOSPHORUS kg/ha

0

0-10

0-10

10

10-20

10-20

10-20 kg P is equivalent to 110-220 kg of superphosphate or 50-100 kg of superking.

10-60 kg N is equivalent to 18-110 kg of urea or 25-150 kg of nitram.

25 kg K is equivalent to 50 kg of muriate of potash or 60 kg of sulphate of potash.

NITROGEN kg/ha

35

35-60

30-40

30-40

30-40

10-30

POTASSIUM kg/ha

0

0

0

0

25

0-25

� I

""'

6-6

Nitrogen requirements depend on the cropping history and soil moisture reserves. Soils in groups 1 and 2 have moderate to high levels of plant available water capacity; those in groups 3,4 and 5

have moderate levels; and those in group 6 have moderate to low levels. Recommended rates of nitrogen have been adjusted to effectively utilise the likely moisture reserves of the soil. Application of nitrogen on soils with a low plant available water capacity, may result in lush vegetative growth, thus depleting soil moisture reserves before crop maturity, particularly if early rain is followed by a dry period. Nitrogen applications are, therefore, safer on grazing crops on the soils of groups 3, 4, 5 and 6 (in Table 6 .3). Nitrogen is not essential for fodder legumes but may give a stimulus to early growth. Nitrogen has to be applied through alternate drills of the combine to avoid damage to the legume seed through contact.

In climatic rates of nitrogen may rate should be used.

zone A, with a higher rainfall, the higher be used, while in climatic zone C the lower These levels will produce economic returns

given favourable seasons.

6.3 HORTICULTURAL CROPS

6.3.1 Smal I Crops

The major small crops grown in the district (including the Toowoomba city area) are lettuce, celery, carrots, cauliflowers, cabbage and broccoli. These crops, apart from carrots, prefer well drained loams and the Ravensbourne, Palmtree and Pechey AMUs of the Basaltic Red Soils LRA are particularly suited. Carrots are mainly grown on the black soils. Most AMUs of the Marburgs LRA are unsuitable because of the hard setting surface and poor subsoil drainage.

These crops are mostly grown in climatic zones Al and A2 where, because of the relatively cool temperatures, summer production can be undertaken.

Expansion of the small crop industry is restricted by the availability of water for irrigation.

6.3.2 Tree and Vine Crops

Avocados and kiwifruit are the main tree crops. Peaches, nectarines, apricots and grapes are also grown.

Avocados, because they can be quickly set back if a large part of their root system is in waterlogged soil for even very short periods, require soils with unimpeded drainage to at least 1.5 m. Some AMUs of the Basaltic Red Soils LRA are therefore most suited. Growers on marginal soils are using a combination of hilling and smaller, precocious varieties, but the life expectancy of the avocados on these soils is only 10 to 12 years.

6-7

Other fruitcrops can be grown successfully on soils with unimpeded drainage to 1 m. Again the most suitable soils are the Ravensbourne, Palmtree and Pechey AMUs of the Basaltic Red Soils LRA and the CDP (TC) in the Granites LRA. Shallower soils (75-100 em) may be used if surface drainage is good, but are not recommended.

6. 4 PASTURES

6.4 0 1 Native Pastures

The predominant native pasture species for the district are pitted blue grass, Queensland blue grass, kangaroo grass and Chloris species. Paspalum has also naturalized in the area. Overgrazing of these pastures is leading to an increase in rat's tail grass, love grass, wire grasses and blady grass.

Pasture growth can be increased by using nitrogenous fertilizers, as shown in a trial near Avenglen (see Appendix XV). However, application of nitrogen fertilizer is unlikely to be economic for most AMUs. The same trial indicated that contour ripping does not increase pasture production. Pasture furrows are also unlikely to be of economic benefit.

6.4.2 Improved Pastures

Pasture improvement is recommended on all soils apart from those with a shallow effective soil depth in the Marburgs, Granites and Metamorphics LRAs (FS I (TC), CS I (TC), FMI (TC), CMI (TC)). The persistence and economics of improved pastures on these soils are doubtful.

In general, Rhodes grass with Siratro is recommended for those soils with a low fertility status and Rhodes grass and green panic with lucerne and Siratro for those soils with a high fertility status. Kikuyu and white clover can be used in climatic zone A, but require high inputs of fertilizer. Codes, which indicate suitable improved pasture specie combinations are listed in Table 6.4 for each AMU in each climatic zone. The improved pasture species within each code are listed in Table 6.5. In addition, suitable improved pasture species for the climatic zones are listed for each AMU in Chapter 11. A summary of the potential of the major pasture species suitable for the district is presented in Appendix XIV.

Fertilizer recommendations for both establishment and maintenance of improved pastures are listed in Table 6.6 (modified from Cull, 1972).

6-8

TABLE 6.4 SUITABLE IMPROVED PASTURE SPECIE COMBINATIONS

{BY COVES -SEE TABLE 6.5 FOR INTERPRETATION)

FOR THE AMI.l{, IN EACH CLIMATIC ZONE

LRA AMU

IMPROVED PASTURE SPECIE COMBINATION FOR TilE CLIMATIC ZONE OF

Metamorphics

Granites

Marburgs

Basalt West

Basalt East

Basal tic Red Soils

Alluvium

CSI (TC) M CSI (U) M CS-MP (TC) M FS-MP(TC) M

CSI (U) Gr CMI (U) Gr CS-MP (TC) Gr CDP (TC) Gr

FSI (TC) and CSI(TC) MF FSI (U) and CSI (U) MF FMH(TC) MF FS-MP(TC) MF CMI (TC) MF CDI(TC) MF CSH (TC) MF and CMH (TC) MF CS-MP(TC) MS FS-MP (TC) MS

Kenmuir Purrawunda

BSs BSd BFs BFd BFwd

Palmtree Pinelands 1 and 2 Pechey Cabarlah Geham Ravens bourne Merritts

Waco Als Alw Alh

Al

NR NR 1. 3.0 1.3 .1

NR 1.2 .0 1.3.0 1.3.0

NR NR 1.3.0 1. 3.1 1.1.0 1.3.0 1.3.0 1.3.2 1.3. 2

1.4 .2 1.4 .2 1.4 .1 1.4.1 1.4.1 1.1.2 1.4.1

NR not recommended for improved pastures = soil does not occur in the climatic zone

A2

NR NR 2 .1.0 2 .1.1

NR 1.2 .0 2.1.0 2 .1.0

NR NR 2.1.0 2.1.1 1.1.0 1.3.0 1.3.0 2.1.2 2 .1.2

2.2.2 2.2.2 2.2.1 1.4.1 1.4.1 2.1.2 2.2.1

6.2.1 6.1.1 6.1.1 6 .1.0

B

NR 5 3. 2.0 3.2.0

5 4 .1.0 3.2.0 3.2.0

N R 5 3.2.0 3.2.0 4.1.0 3.6.0 3.6.0 3.2.1 3.2.1

3.5.1 3.5.1 3.5.1 3.5.1 3.5.0

3.4.1 3.4.1 3.4.0 3.3.0 3.3.0 3.1.1 3.4.0

6.2.0 6 .1.0 6 .1.0 6.1.2

NR 5

c

4 .1.0 4.1.0 4.1.0 4. 2.0 4.2.0 4.2.1 4.2.1

6.0.0 6.2.0

6.2 .0.

6-9

TABLE 6.5 IMPROVED PASTURE SPECIES FOR

1st Digit

1. Rhodes grass, paspalum

2. Rhodes grass, paspalum, lucerne

3. Rhodes grass, paspalum, creeping blue grass, Siratro, Kazungula Setaria

4. Rhodes grass, creeping blue grass, Siratro

5. Siratro and/or creeping blue grass

6. Rhodes grass, green panic, medics, lucerne, creeping blue grass

EXAMPLE: 1.2.1 is

THE COVES IN TABLE 6.4

SPECIES FOR

2nd Digit

1-medics (but only if soil pH > 6.5) 2-medics (but only if soil pH> 6.5), white clover 3-medics (but only if soil pH> 6.5}, white clover, fescue, phalaris 4-white clover, fescue phalaris

1-medics (but only if soil pH> 6.5), fescue, phalaris, white clover 2-fescue, phalaris, white clover

1-medics (but only if soil pH> 6.5} 2-medics (but only if soil pH> 6.5), lucerne, white clover 3-whi te clover 4-white clever, lucerne 5-white, clover, lucerne, medics 6-medics (but only if soil pH> 6.5}, lucerne

1-medics (but only if soil pH > 6. 5) 2-medics (but only if soil pH > 6.5), lucerne

0 -1-white clover, paspalum 2-Makarikari grass (cv. Bambatsi), Columbus grass

Rhodes grass, paspalum, medics (but only if the soil pH> 6.5} and kikuyu (if N is applied} .

3rd Digit

0 -1-kikuyu (if N is applied) 2-kikuyu, green panic

0 -1-kikuyu (if N is applied) 2-kikuyu, green panic

0 -1-green panic

0 -1-green panic

0 -1-kikuyu 2-Siratro

��

TABLE 6.6

LRA AMUs

Basalt West All soils

Basalt East All soils

Basal tic Red Pechey, Cabarlah, Soils Geham, Merritts

Palmtree

Ravens bourne, Pinelands

Marburgs and Ms(scrub) Metamorphics

csi; FSI, CMI, FMI

Other soils

Granites CSI, CMI

Other soils

responses not ·recorded.

GENERALISEV FERTILIZER RECOMMEN VATIONS FOR IMPROVEV

PASTURES IN THE C ROW'S NEST VISTRICT

ESTABLISHMENT

N p K S* Mo* Lime N kg/ha Pellet

0-20 - 0-40 - No -

0-35 0-20 X 0-40 ? No 15-25

10-35 40-60 X 40 Yes Yes 10-25

--

10-25 20-40 X 20-40 Yes ? 15-25

0-25 10-40 X ? Yes No 0-25

? ? ? ? ? ? ?

ns ns ns ns ns ns ns

10-25 20-60 X 20-60 Yes ? 15-35

ns ns ns ns ns ns ns

10-25 40-60 ? 40 Yes Yes 0-25

MAINTENANCE

p K kg/ha

0-10

0-10 X

10-20 X

10-20 X

0-10 X

? ?

ns ns

10-20 ?

ns ns

10-20 ?

ns not suitable for sown pastures.

s

0-20

0-20

10-20

10-20

0-10

?

ns

10-20

ns

10-20

X responses have bee�1 recorded on old cultivation. * Mo and S are generally only required when

? requirements are unknown·. legumes are used.

The need for lime pelleting of medic seed is also a question on some sites, even in those where it is recommended at present.

G '

"-' "'

6-11

6.4.3 Pasture Management

Grazing management should not only aim at maximum animal production but should also prevent pasture and soil degradation.

(i) Grazing Management

Recommended carrying capacities for both native and improved pastures to maintain an adequate ground cover are presented in Table 6.7. Stocking rates should be flexible to allow for adjustment according to the season. The Metamorphic soils mostly occur on steep land slopes and are generally not suited for development.

Sown pastures require spelling during summer. An ungrazed period of 2-4 months, at least once in every 4 years will improve pasture persistence (Scattini, pers. comm. ) . Pastures on eroded land should be rested every third growing season.

On unstable soils, such as CSI (TC) and FSI (TC) , pastures should be grazed after rain and then destocked. Browse species and quick maturing ephemerals can be utilised after rain. If pastures on these soils are continuously grazed, gully lines which produce better feed will be preferred by stock and will become unstable. Serious gully erosion will result. The overgrazing of gully lines together with the location of watering points in the gully are thought to be the main causes of gully erosion in pastures on these soils.

( ii) Burning Strategy

Regular burning (usually in August) of pastures on grazing properties in the eastern half of the district is carried out. Burning of pastures on dairy farms is not common.

Burning to remove rank grass every two to three years should be sufficient. It is best carried out soon after rain in spring to allow the grass to grow and provide protection against storms in summer. Burning after rain gives a fire of low intensity, which leaves some litter on the ground. Attempts to control lantana with burning have not been successful.

Areas that are particularly prone to soil erosion, such as areas with CSI(TC) and FSI(TC) soils should not be burned except under the most favourable conditions.

When burning off, fire breaks should be constructed to prevent the fire reaching areas that should not be burned, such as areas on steep land slopes with erodible soils.

The use of urea and molasses licks allows the better use of old or rank, low quality pasture and could reduce the need to burn.

6-12

TABLE 6. 7 RECOMMENDED CARRYING CAPACITIES

FOR THE SOILS OF THE LANV RESOURCE AREAS

CLIMATIC SOIL GROUP PASTURE TYPE

RECOMMENDED

*

**

+

++

ZONE CARRYING CAPACITY ha/beast

Al Basal tic Red

B

c

Soils 1* Improved pasture 0.7 2** Improved pasture and

fertilizer 0.7 Native pasture 1. 1

Marburgs 1+ Native pasture/timber 4 - 6

Basal tic Red Soils 1 Improved pasture 0.9

2 Improved pasture and fertilizer 0.9

Native pasture 1.8 Mar burgs 1 Native pasture/timber 4 - 6

Basaltic Red Soils 1 Improved pasture 1. 1

2 Improved pasture and fertilizer 1. 2

Native pasture 2. 4 Basalt East Improved pasture 1. 2 - 1. 6

Native pasture 2.0 - 2. 4 Mar burgs 1 Native pasture/timber 5 - 7

2++ Improved pasture 1. 2 - 1.8 Native pasture 2.4 - 3.6

Granites Improved pasture 1.6 Native pasture 2 . 4

Metamorphics Native pasture/timber 5 - 9

Basalt West Native pasture 2. 4 Marburgs 1 Native pasture/timber 5 - 7

2 Improved pasture 1.4 - 2.0 Native pasture 2.4 - 3.6

Basaltic Red Soils 1 are the scrub soils - Ravensbourne, Pinelands.

Basaltic Red Soils 2 are the forest soils - Merritts, Geham, Cabarlah, Pechey, Palmtree.

Marburgs 1 are the shallow Marburgs - FSI (TC) , CSI (TC) , FSI (U) and CSI (U) .

Marburgs 2 are the deeper Marburgs.

The soils of the Granites LRA have not been separated into groups. In most cases shallow and deep soils will occur on the same property.

6-13

(iii) Stock Watering Points

Stock watering points should be carefully selected to avoid stock tracks concentrating runoff water and causing soil erosion.

Watering points should, therefore, be selected on low sloping areas and water from waterholes or dams should be pumped to troughs on the adjacent flat areas. This is particularly important where waterholes are situated in gullies with steep side slopes or on soils with unstable subsoils (FSI (TC), CSI (TC) , FeU (TC), CMI (TC)).

(iv) Fencing

Paddock size should allow control of stock and implementation o f a grazing system. Gates should be located as much as possible on flat ground, away from drainage lines.

(v) Laneways

Laneways on dairy farms are often badly eroded. Reclamation is generally not practical. Whoa-boys or check banks* discharging into contour banks or pasture land are recommended.

* Whoa-boys or check banks a small diversion drain across a roadway.

7-1

7. SPECIFICATIONS FOR RUNOFF

CONTROL STRUCTURES

7.1 INTRODUCTION

In most sloping situations in the Crow•s Nest District, runoff control structures will be required to intercept runoff water before it can concentrate and reach scouring velocities. The design principles for runoff control structures are described in Part 9 of the Queensland Soil Conservation Handbook. Only the actual specifications, the reasoning for these specifications, the construction techniques and maintenance requirements for structures in the Grow's Nest District are listed in this technical manual.

7.2 RUNOFF ESTIMATION

The Rational Method is used to estimate surface runoff. In the Grow's Nest District it provides satisfactory results with the following exceptions:

(i) Diversion banks carrying runoff from grassland are overdesigned. In this cas� the runoff coefficient for grassland may be overestimated.

(ii) Waterways in large catchments may be overdesigned. This is possibly because the design storm only occurs in parts of the catchment.

Runoff coefficients for use in the Rational Method vary with the soil, land use, landform and rainfall intensity. The AMUs of the district have been grouped into three runoff coefficient soil categories - A to C (see Table 7. 2.1). Category A are those soils with high rates of infiltration under saturated conditions and category G are those soils with low infiltration rates under saturated conditions. Runoff coefficients for a range of land uses and land forms for the soil categories are presented in Table 7.2. 2.

To facilitate runoff estimates for waterway and diversion bank design, the time of concentration for a range of cover conditions and land slopes and in addition the rainfall intensity for the 1 in 10 design frequency (for use in the Rational Method) are presented in Appendix IV.

Runoff to be catered for at the contour bank outlet would be expected to depend on land slope, bank spacing (standard or double standard), channel velocity, drainage design rating* and bank length. Peak runoff for these variables is presented for a runoff coefficient of 0.5 for the 1 in 10 design frequency in Appendix V. It is apparent from the values that channel velocity and drainage rating do not significantly influence runoff and that slopes > 2% behave similarly.

* Drainage Design Rating see Section 7.4. 3.

TABLE 7.2.7

LRA

Basalt West

Basalt East

Basal tic Red Soils

Marburgs

Granites

Metamorphics

Alluvium

* A � permeable soil;

7-2

RUNOFF COEFFICIENT SOIL CATEGORIES

FOR THE AMUI

AMU RUNOFF COEFFICIENT

SOIL CATEGORY

Kenmuir B*

Purrawunda B

BSs B BFs B BSd B BFd B BFwd B

Cabarlah B Pechey B Palm tree A*

Geham B Ravens bourne A Pinelands 1 and 2 A Merritts B

CSI (TC) MF c*

FSI (TC) MF c CSI (U) MF c FSI (U) MF c CMI (TC) MF c CDI (TC) MF B CSH (TC) MF B CMH (TC) MF B FMH (TC) MF c CS-MP (TC) MS B FS-MP (TC) MF B FS-MP (TC) MS B

CSI (U) Gr c CMI (U) Gr B CS-MP (TC) Gr B CDP (TC) Gr A

CSI (TC) M c CST (U) M c CS-MP (TC) M B FS-MP (G) M A

Waco B Al s B Al w B Al h B

B � medium; c � impermeable soil.

7-3

TABLE 7.2.2 RUNOFF CO-EFFICIENTS FOR A RANGE OF LANV USES ANV

LANVFORMS FOR THE RUNOFF CO-EFFICIENT SOIL CATEGORIES

RUNOFF CO-EFFICIENT RUNOFF CO-EFFICIENT FOR SOIL CATEGORY

LAND USE LANDFORM A DESIGN FREQUENCY OF

(Table 7.2.1) 1:10 1:100

A Timber/Pasture Rolling < 10% 0.1 0.2

(permeable soil) Hilly > 10% 0.1 0.2

Cultivation Rolling < 10% 0.3 0.4

Hilly > 10% 0.4 0.6

B Timber /Pasture Rolling < 10% 0.2 0.3 (medium)

Hilly > 10% 0.3 0.4


Hilly > 10% 0.6 0.7

c Timber/Pasture Rolling < 10% 0.3 0.5 (impermeable soil)

10% 0.5 0.7 Hilly >


Hilly > 10% 0.7 0.9

------ ··---·-------·

7-4

7.3 THE RUNOFF CONTROL STRUCTURES

In the Crow's Nest District the major structures used for runoff control are listed below. In general these structures are only used in cropped situations on grain and fodder crops, small crops, row crops, and tree and vine crops. They are generally not considered economic in pasture land except in crop/pasture rotations or for the rehabilitation of eroded pasture land.

The major structures/measures used are:

(i) Contour banks for grain cropping areas, row crops and in some cases small crops.

(ii) Modified contour banks/beds for small crops.

(iii)

(iv)

(v)

(vi)

Normal contour banks may be used for small crops.

Diversion banks and pondage banks.

Spreader channels to spread concentrated water flow in grassland.

Waterways.

Other measures such as grass strips, contour ripping and pasture furrows.

7-5

7.4 SPECIFICATIONS FOR CONTOUR BANKS

Contour banks are used predominantly in grain and fodder cropping areas. Summary specification; for contour banks are presented in Table 7. 4.1 - summary sheets l and 2.

or

or

or

7.4. 1 Suitability of Soi Is and Sites for Contour Bank Construction

Contour banks should not be constructed on:

(i) Those texture contrast soils with both impermeable subsoils and with shallow to moderately deep A horizons - FSI (TC), CSI (TC), FMI (TC) and CMI(TC). Construction of contour banks on these soils

(ii)

(iii)

(i v)

will lead to exposure of the impermeable, dispersible and highly erodible B horizon. Exposure of this B horizon will lead to tunnel erosion and gullying. If it is absolutely necessary, banks may be constructed from the bottom side on FMI (TC) and CMI (TC).

Those shallow to moderately deep, uniform soils overlying rock - CSI (U), FSI (U), CMI (U), FMI (U), Kenmuir, BSs, BFs and Cabarlah. The shallow soil depth does not provide sufficient soil for contour bank construction.

In areas where stable contour bank outlets into a creek or drainage line are not available. This is mostly a problem on texture contrast soils e.g. FMH (TC)MF. This problem can be overcome by constructing a waterway with a safe outlet in a downstream position, parallel to the creek or drainage line.

On very steep slopes - > 15%.

7.4.2 Contour Bank Type

(i) Broad base cultivated contour banks or broad base top side contour banks are recommended for land slopes up to 6% on those soils that may crack sufficiently to cause contour bank failure. Such soils include the

and

(a)

(b)

Purrawunda

Waco.

Broad base grassed contour banks are recommended on the Purrawunda if slopes exceed 6%. This is because channel capacity is difficult to achieve and the construction costs per hectare, due to the close spacings on steep land slopes, are prohibitive for broad base cultivated banks above 6% land slope.

7-6

TABLE 7.4.1 SUMMARY SPECIFICATIONS FOR CONTOUR BANKS SHEET

SOIL l1INIMUM DRAINAGE MAXIMUM

LRA AMU SUITABILITY SPECIFICATIONS DESIGN PERMISSIBLE

.FOR TYPE RATING VELOCITY (m/sec)

Basalt West Kenmuir ns 7.4

Purrawunda s BBTS 6.8 0.5

Basalt East BSs ns NB 7.4 0.5

BPs s NB 7.4 0.5

BSd s NB 6.8 0.5

BPd s NB 6.8 0.5

BPwd s NB 6.8 0.5

Basal tic Red Cabarlah ns NB 8.0 0.6

Soils Pechey s NB 8.0 0.6

Palm tree s NB 8.0 0.6

Geham s NB 8.0 0.5

Ravens bourne s NB 8.6 0.6

Pinelands 1 and 2 s NB 8.6 0.6

Merritts s NB 6.8 0.5

Mar burgs CSI (TC) MF ns 6.2 0.5

PSI (TC) MF ns 6.2 0.5

CSI (U) MF ns 6.8 0.5

PSI (U) MP ns 6.8 0.5

CMI (TC) MP ls NB 6.8 0.5

cor (TC) MP s NB 6.8 0.5

CSH (TC) MF s NB 6.8 0.5

CMH (TC) MP s NB 6.8 0.5

PMH (TC) MF s NB 6.2 0.5

CS-MP (TC) MS s NB 7.4 0.5

FS-MP (TC) MF s NB 7.4 0.5

FS-MP (TC) MS s NB 7.4 0.5

Granites CSI (U) Gr ns 6.8 0.5

CMI (U) Gr ls NB 7.4 0.5

CS-MP (TC) Gr s NB 7.4 0.5

COP (TC) Gr s NB 8.6 0.5

Metamorphic s CSI (TC) M ns 6.2 0.5

CSI (U) M ns 6.8 0.5

CS-MP (TC) M s NB 7.4 O:S

FS-MP (G) M s NB 8.0 0.6

Alluvi urn Waco s BBTS 0.5

Al s s NB 0.5

AI w s NB 0.5

Al h s NB 0.5

·-------·

7-7

TABLE 7.4.1 SUMMARY SPECIFICATIONS FOR

CONTOUR BANKS - SHEET Z

(i) Contour Bank Spacing

(a) Standard spacing VI = 0.15 (s + x) *

(b) Double standard spacing VI = 0. 3 (s + x) *

* for land slopes of 2 to 7%.

(ii) Constructed Bank Height

(iii)

H = d+ f+ s equation 7. 3

d = design depth of flow - see Appendix VI

f = freeboard 0 . 15 m

s = settlement (%of (d + f) depending on the AMU).

Bank Length

Normal maximum bank length up to 600 m. Banks up to l 200 m can be used provided gradients are reduced and bank heights increased.

(iv) Design Frequency - 1 in 10.

(v) Maintenance

Remove silt from channels to maintain bank design capacity.

and

7-8

(ii) Narrow base banks are adequate on all other soils suitable for contour bank construction. BF d, BSd and Merritts AMUs crack to a certain extent but most of these soils occur on steep land slopes ( > 6%) and narrow base banks appear adequate.

7.4. 3 Contour Bank Spacing

Contour banks are spaced at:

(i) Standard spacing (ss) which is determined by

(ii)

VI � 0. 15 (s + x) .... ..... equation 7.1

Double standard spacing (ds) which is determined by VI � 0. 3 (s + x) ...... . equation 7.2 where VI � vertical interval (m) between contour banks.

s � land slope (%) x � drainage design rating which is tabulated

for each AMU in Table 7.4. 2.

Standard spacing will prevent rilling under bare fallow conditions with stubble removed for the 1 in 1 0 year storm. Double standard spacing will prevent rilling under bare fallow conditions with stubble retained for the 1 in 10 year storm.

This method should not be used to determine the vertical interval for steep or low land slopes.

On steep* land slopes the horizontal distance is determined as follows:

(i)

(ii)

(iii)

For land slopes of 7 - 10% a horizontal distance of 31 m is used for all soils.

For land slopes of 10 - 12% a horizontal distance of 31 m is used for soils with a drainage design rating> 7.0 and 24 m for soils with a drainage design rating < 7.0.

For land slopes greater than 12% a horizontal distance of 24 m is used for all soils.

For land slopes < 2% a standard horizontal distance of 120 m is used.

Bank spacing may have to be varied to suit the availability of stable contour bank outlets. This is especially a problem on texture contrast soils with outlets into creeks that have steep side slopes. Double standard spacing should not be exceeded if bank spacing is varied for this reason. If stable outlets at suitable spacings are not available, an auxillary waterway parallel to the main watercourse will be required.

Standard spacing should not be exceeded for parallel banks as some sections have higher than acceptable gradients.

* Land slope is extremely variable in steep areas and the estimated

steepest land slope for an area is used to derive the horizontal

distance.

7-9

TABLE 7.4.Z VRAINAGE VESIGN RATINGS FOR THE AMU\

LRA AMU DRAINAGE DESIGN

RATING

Basalt West Kenmuir 7.4 Purrawunda 6. 8

Basalt East BSs 7.4 BFs 7.4 BSd 6.8 BFd 6. 8 BFwd 6.8

Basaltic Red Soils Cabarlah 8.0 Pechey 8.0 Palmtree 8.0 Geham 8.0 Ravens bourne 8.6 Pinelands 1 and 2 8.6 Merritts 6. 8

Marburgs CSI (TC) MF 6.2 FSI (TC) MF 6.2 CSI (U) MF 6.8 FSI (U) MF 6. 8 CMI (TC) MF 6. 8 CDI (TC) MF 6.8 CSH (TC) MF 6.8 CMH (TC) MF 6. 8 FMH (TC) MF 6.2 CS-MP (TC) MS 7.4 FS-MP (TC) MF 7.4 FS-MP (TC) MS 7.4

Granites CSI (U) Gr 6. 8 CMI (U) Gr 7.4 CS-MP (TC) Gr 7.4 COP (TC) Gr 8.6

Metamorphics CSI (TC) M 6.2 CSI (U) M 6. 8 CS-MF (TC) M 7.4 FS-MP (G) M 8.0

Alluvium Waco NA Al s NA Al w NA Al h NA

NA � Not Applicable - These soils occur on slopes < 2% for which a standard horizontal distance of 120 m is used.

7-10

7.4.4 Maximum Permissible Channel Velocity

Maximum permissible bare channel velocities for contour banks are presented in Table 7.4.3.

TABLE 7.4.3 MAXIMUM PERMISSIBLE VELOCITIES

FOR BARE EARTH CONTOUR BANK CHANNELS

AMUs

Merritts, Geham and AMUs of the Basalt West, Basalt East, Granites, Metamorphics and Marburgs LRAs with the exception of FS-MP (G) .

FS-MP(G) and AMUs of the Basaltic Red Soils LRA with the exception of Merritts and Geham.

7.4.5 Channel Gradient

MAXIMUM PERMISSIBLE VELOCITY m/sec

0. so

0.60

(a) Graded Bo:riks - narrOZJ base contour banks

Maximum channel gradients that should not be exceeded are indicated in Appendix VI.

Variable gradients starting with 0.1% and finishing with 0.3% are recommended for land slopes < 7%. On land slopes of < 2%, a maximum gradient of 0.2% may be used, as it is desirable to keep the channel gradient to < 10% of the land slope. On land slopes > 7%, a constant channel gradient of 0.4% is used for bank lengths < 300 m and of 0.3% for bank lengths > 300 m. The constant and steeper channel gradients are used on steep land slopes for the following reasons:

(i) Distance between survey points on steep land slopes is reduced from 30 to 15 m to prevent the occurrence of irregularities. There is less error in surveying steeper channel gradients over this shorter distance.

(ii) During construction, irregularities in the channel are more likely to occur with low channel gradients. This is not a problem on land slopes < 7%.

Where a contour bank crosses a depression line (natural or eroded), the channel gradient �ay be increased to a maximum of 1.5%. This is done because:

(i) Contour banks are taken directly across depression lines to avoid very sharp curves.

(ii) Construction of a contour bank across a depression line will require extra soil which will lead to a deeper excavation in the channel. Increasing the channel gradient will prevent ponding in this area.

7-11

(b) LeveL B a:nks

Level banks may be used on permeable soils (runoff co-efficient category A only) when runoff retention is required by the landholder. Wetness is a problem in the channel and level banks are only generally recommended in pasture l and.

(c) Pa:mlleL Ba:nks

For parallel banks, channel gradient will vary from l evel to very steep. Desirable maximum gradient depends on the permissible runoff velocity in the channel, which in turn is governed by the AMU . Parallel layouts have been used for row crops such as potatoes and onions where machinery requirments demand it.

(d) Outlet Gradients

Channel gradients used in the outlet area of contour banks vary:

(i) If the bottom of the contour bank channel is lower than the outlet area and the outlet area is or will be grassed, the bank is turned down sharply in the last 3 m, giving the channel an outlet gradient of approximately 60% of the land slope.

(ii) If the outlet area is lower than the channel or if the channel will be cultivated right up to the outlet area, the outlet gradient should not exceed the maximum gradient of the bank.

7. 4. 6 Depth of Flow - Narrow Base Contour Banks

The design depth of flow in contour banks is influenced by:

(i)

(ii)

(iii)

(iv)

Estimated peak runoff between banks.

Channel gradient which is governed by maximum permissible velocity.

Cross sectional area which is governed by land slope and

Channel shape. Field checking of the shape of contour banks 5 years after construction showed most banks to have a triangular shape. Depth of flow in this manual is based on a triangular cross section.

The design depth of flow for the 1 in 1 0 storm based on these variables and a triangular shape are presented for narrow base contour banks in Appendix VI. In addition the channel velocity and peak runoff is presented for the dep th of flow.

7-12

7.4. 7 Con structed Bank Height

Constructed bank height is determined from the equation

H � d + f + s .... . . . . equation 7.3

where H d f s

�

�

�

constructed bank height (m) before settlement design depth of flow (m) freeboard - 0. 1 5 m allowance for settlement.

Design depth of flow for narrow base contour banks is shown in Appendix VI.

Freeboard is added to compensate for:

(i)

(ii)

(iii)

Irregularities occurring during construction of the bank.

Build-up of runoff (standing wave) at sharp curves in the bank.

Hydraulic pressure occurring on the narrow top section of the bank.

The addition of 0.1 5 m of freeboard to the depth of flow will increase the design frequency and the design velocity.

Settlement (% of d + f) depends on the construction technique and AMU . Settlement values are presented in Table 7. 4. 4.

TABLE 7.4.4 SETTLEMENT VALUES (%] FOR CONTOUR BANKS

Cracking Soils Non Cracking Soils

DOZER CONSTRUCTION

30 2 5

7.4.8 Contour Bank Length

GRADER CONSTRUCTION

25 2 0

Bank length normally does not exceed 8 0 0 m. To facilitate farm management it is sometimes desirable to construct longer banks. The design depth of flow for bank lengths up to 1 200 m is provided in Appendix VI.

Banks longer than 1 ZOO m must be individually designed and will require low channel gradients to keep the velocity of the increased flow from the larger catchment between the banks within permissible limits. Longer banks will result in higher banks which become expensive to construct.

7-13

7.4.9 Contour Bank Failure/Design Frequency

Bank capacity is designed for the 1 in 10 return period. However by adding O.lSm of freeboard to the design depth of flow, the actual return period may exceed 1 in 100. For this higher return period, channel velocity will exceed the maximum permissible velocity. This higher velocity, which occurs only occasionally has been observed not to cause permanent damage to the channel.

In practice, bank failure occurs more frequently than the 1 in 1 0 0 return period for two possible reasons:

(i) Interbank erosion deposits silt in the channel, thus reducing its capacity.

(ii) Waterways or natural depressions for the 1 in 10 or 1 in SO design frequency may not be able to handle the 1 in 100 flow, thus causing the runoff to back up, overtop and break contour banks.

Contour banks performed much better than expected during the high intensity rainfall events of February, 1981 in the district. This was probably due to the generally short length of the contour bank, the use of standard spacing and the channel gradient of 0.4% used on the steep land slopes. Some banks failed at the outlet, because the natural depressions could not handle the neak flow.

7.4.10 Contour Bank Construction

Contour banks should not be constructed until waterways are properly grassed up. Recommended construction techniques are explained in an advisory leaflet by Lehmann and Bartels (1978a).

Dozer blades and grader blades have both been used successfully for the construction of contour banks. Generally, a dozer blade is preferred for contour banks.

It may sometimes be necessary to construct contour banks on soils considered not suitable for bank construction (see Section 7.4.1) (e.g. a diversion bank to divert runoff from an eroding gully). This requires the following special construction techniques (Roberts pers. comm.).

The topsoil is pushed uphill first and the bank constructed with the subsoil. After construction of the bank, the topsoil is pushed back into the channel and onto the front slope of the bank. Ideally, the bank should be compacted as much as possible during construction to prevent dispersion. A grader built bank will compact better than a dozer built bank. This construction method is expensive and cannot be recommended for soils suited to normal construction. There is also a higher than normal risk of failure of banks on these unsuitable soils.

7-14

7. 4. 11 Contour Bank Maintenance

Interbank erosion will deposit silt in the channel and reduce its capacity. Channel capacity of contour banks can be maintained by:

(i)

(ii)

Reducing interbank erosion with stubble mulching and other cultural practices.

Periodic removal (at 5 - 10 year intervals) of silt from the channel. Broad base contour banks require more frequent maintenance, because

-- _:tluo__cons:tant_culthcation_Q£ t_ae __ bank reduces __ i ts capacity.

7-15

7.5 SPECIFICATIONS FOR MODIFIED CONTOUR BANKS/BEDS FOR SMALL CROPS

In most situations modified contour banks/beds on the straight and para11e1 may be used for small crops to facilitate farming operations such as irrigating and spraying. These structures are basically contour banks/beds or ditches with grassed channels and with access tracks which link up with the farm roads. A typical soil conservation layout for a small crop farm using modified contour banks/beds is shown in Figure 7.1.

Normal contour banks (both graded and parallel) may be used for small crops but do have disadvantages associated with some farm operations. Summary specifications for modified contour banks/ beds are presented in Table 7.5. 1 - summary sheets 1 and 2.

7. 5. 1 Suitabi I ity of Soi Is

Those soils that are suitable for the construction of normal contour banks are suitable for modified contour banks/beds (Section 7.4.1).

7.5. 2 Modified Contour Bank/Bed Type

Four types are used (Figure 7.2).

(i) The beds are built up in the middle as shown in the cross section in Figure 7.2. This type is only suitable on land slopes less than 2%. On steeper slopes the spacing between channe1s (bed width) has to be reduced as excessive earth movement will be required to form a bank that is high enough.

(ii) Parallel and straight contour banks with vehicle tracks located in the channel as shown in

(iii)

Figure 7.2. This type is suitable for all land slopes but is not suited to very steep channel gradients.

Parallel and straight contour banks with vehicle tracks located on the bottom side of the bank (see Figure 7.2). This type is suitable for most land slopes and channel gradients.

(iv) Parallel sub surface ditches are used instead of banks with vehicle tracks stradling the ditch as shown in Figure 7.2. Sub surface ditches are recommended for poorly drained sites or soils but have not been fully tested as yet in the district.

7-16

FIGURE 7.1 TYPICAL SOIL CONSERVATION LAYOUT

FOR A SMALL CROP FARM

t ' - -t Tr

� "'" + +

+ + + r- +

� �J 1-

'

�[ 1- � ; -J-

I

� I B " I I

r � � I 1-I

"

� l I I I I t

--..::::..__- I - - -- ---..!- "'-- I __ -..; __ --

�c,�· .... t'"t"-t .._ ......... ..... _

DIVERSION BANK ... ......... "i'r."'"'"'"'"""' INVERT IN WATERWAY ..

BANK or DRAIN COMBINED WITH FEEDER TRACK ..

WATERWAYS.. . .... n. I I 1.-1 I I

A Major natural depression dovolopod as w.t.rw"'

B Small depression developed as waterway that can be crossed with implements

MAIN ACCESS ROAD ....

UNDER GROUND MAIN ..

IRRIGATION LINE ..

BUILDING

CATCHMENT RUNOFF ..

+ + • ,...,..,

,�

-

-

*

•

' ' '

Land Slope

7-17

TABLE 7. 5.1 SUMMARY SPECIFICATIONS FOR

MOVIFIEV CONTOUR BANKS/BEVS - SHEET 1

MAXIMUM

LRA AMU SOIL PERMISSIBLE

SUITABILITY VELOCITY ROW FURROWS

(m/sec)

Basalt West Kenmuir ns Purrawunda s 0.5

Basalt East BSs ns 0.5 BFs s 0.5 BSd s 0.5 BFd s 0. 5 BFwd s 0.5

Basaltic Red Soils Cabarlah ns Pechey s 0.6 Palmtree s 0.6 Geham s 0.6 Ravens bourne s 0.6 Pinelands 1 and 2 s 0. 6 Merritts s 0.5

Marburgs CSI (TC) MF ns FSI (TC) MF ns CSI (U) MF ns FSI (U) MF ns CMI (TC) MF ls 0.5 CDI (TC) MF s 0.5 CSH (TC) MF s 0.5 CMH (TC) MF s 0. 5 FMH (TC) MF s 0.5 CS-MP (TC) MS s 0.5 FS-MP (TC) MF s 0.5 FS-MP (TC) MS s 0.5

Granite s CSI (U) Gr ns CMI (U) Gr ls 0. 5 CS-MP (TC) Gr s 0.5 CDP (TC) Gr s 0.5

Metamorphics CSI (TC) M ns CSI (U) M ns CS-MP (TC) M s 0.5 FS-MP (G) M s 0.5

Alluvium Waco 5 0.5 Al s s 0.5 Al w s 0.5 Al h s 0. 5

s ; suitable; ls ; less suitable; ns ; not suitable.

rnmr--------------------------

7-18


MOVIFIEV CONTOUR BANKS/BEVS - SHEET 2

(i) Spacing

Double standard spacing is recommended VI ; 0.3 (s + x) equation 7.2

(ii) Constructed Bed Height

equation 7.3

d ; design depth of flow - see Appendix VII

s ; settlement(% of d depending on AMU).

(iii) Design Frequency

1 in 10.

"�-------------- -------·---�-- .--- ---

7-19

f!GURf 1.t MOVIFIEV CONTOUR BANK/BfV TYPES

FOR SMALL CROP AREAS

channel

cultivated area

-----�--�-------- -

cultivated area T

d

- - - ------------�--

Type 1

bank

cultivated area

- -- -- -- - -

TY1.Je 2

--- --------- -- --- �

track cultivated area cultivated area

Type 4

d � depth of floW

w � width 6f channel

h � height of bed above the channel

7- 20

7.5.3 Modified Contour Bank/Bed Spacing

Standard spacing is recowNended for those crops requiring a very fine seedbed. Doubl.e standard spacing is adequate for all other crops as the furrows between the hilled crop rows will carry much of the runoff water and the bare fallow period between crops is generally minimal. Distance between banks has to be adjusted to suit multiples of the bed width.

7. 5.4 Maximum Permissible Channel Velocity

Maximum permissible channel velocity for each bed type is presented in Table 7.5.2. The recommended maximum permissible velocity depends on the condition of the channel.

TYPE

1

2

3

4

TABLE 7.5.2 MAXIMUM PERMISSIBLE CHANNEL VELOCITIES

FOR MOVIFIEV CONTOUR BANKS/BEVS FOR SMALL CROPS

CONDITION OF CHANNEL

Some grass, bare fallow at times, cropped at times.

Poor grass cover.

Good grass cover which should be slashed regularly.

Vigorous grass cover which cannot be slashed.

VEGETAL RETARDANCE

CATEGORY

E

E

c

B

MAXIMUM PERMISSIBLE

VELOCITY m/sec

0 .5*

0. 8

1. 7

1.7

* 0. 5 was selected to reduce the scouring risk during the short bare fallow period.

c

7-21

7.5.5 Channel Gradient and Depth of Flow

Channel gradients and the depth of flow for each type are documented in Appendix VII.

7. 5.6 Constructed Bank Height

Constructed bank height is determined by adding an allowance for settlement as set out in Section 7. 4.7. An allowance for freeboard is not needed (see Section 7.4. 7).

7.5.7 Furrow Specifications

(a} Ma;x;imwn Permissible Velocities

The maximum permissible velocity for row furrows is the same as for the bare earth channels in normal contour banks (see Table 7.4.3).

(b) Ma;x;imwn Furr� Gradient

Maximum permissible furrow gradient based on furrow cross sections measured in the field are presented in Table 7.5. 3 for the A�s. The velocities achieved for gradient� from 0.1 to 10% are shown in Appendix VIII.

TABLE 7.5.3 MAXIMUM PERMISSIBLE GRADIENTS FOR ROW

FURROWS FOR THE AMUo COMMONLY USEV FOR SMALL CROPPING

AMUs

Merritts, CMI (U), CDI (U), CVDI (U), CDP (TC) and AMUs of the Basalt East and Basalt West LRAs.

FS-MP (G) and AMUs of the Basaltic Red Soils LRA with the exception of Merritts.

MAXIMUM PERMISSIBLE GRADIENT (%)

3

4. 5

7-22

7.6 ·SPECIFICATIONS FOR DIVERSION BANKS

are: The differences .between contour banks and diversion banks

(i) Diversion banks have grassed channels.

',(ii) . Diversion banks generally maintain. their .. trapezodial cross section after construction.

Diversion banks are used in the Grow's Nest District to:

(i)

(ii)

(iii)

Protect cultivation from runoff from areas higher up the slope.

To divert water into or from farm dams.

To divert water from unstable eroding areas into pasture.

Summary specifications for diversion banks are presented in Table 7. 6. 1 - summary sheets 1 and 2. Those soils not suited to contour bank construction are also unsuitable for the construction of diversion banks (see Section 7. 4. 1). Diversion banks are however, constructed on the Kenmuir, BSs, BFs and Cabarlah.

Grass is present in the channel but growth is often poor due to removal of surface soil during construction. Recommendations are based on natural grass regrowth and not sowing and fertilizing of species. For design purposes the following values are used.

(i)

(ii)

(iii)

Retardance category D with a maximum permissible velocity of 1. 0 m/sec for those suitable soils of the Marburgs, Granites, Metamorphics and Basaltic Red Soils LRAs.

Retardance category C with a maximum permissible velocity of 1. 2 m/sec for the soils of the Basalt East and Basalt West LRAs. These AMUs have a more stable and more fertile subsoil than those in (i) above.

1 in 10 design frequency.

(iv) Where a gully line enters a diversion bank, the channel gradient can be increased by a maximum of 0. 5% for approximately 30 m.

The design specifications fordiversion banks are presented in Appendix IX. The depth of flow, channel width and channel gradient for the peak flow for two retardance values are presented in Table 7. 6. 2. The channel gradient is slightly higher than that recommended for contour banks.

7-23


DIVERSION BANKS - SHEET 1

MAXIMUM

LRA AMU SOIL PERMISSIBLE RETARDANCE SUITABILITY VELOCITY CATEGORY

ra/sec

Basalt West Kenmuir s 1.0 c Purrawunda s 1.2 c

Basalt East BSs s 1.0 c BFs s 1.2 c BSd s 1.2 c BFd s 1.2 c BFwd s 1.2 c

Basaltic Red Cabarlah s 1.0 c Soils Pechey s 1.0 D

Palmtree s 1.0 D Geham s 1.0 D Ravens bourne s 1.0 D Pinelands 1 and 2 s 1.0 D Merritts s 1.0 D

Marburgs CSI (TC) MF ns FSI (TC) MF ns CSI (U) MF ns FSI (U) MF ns CMI (TC) MF ls 1.0 D CDI (TC) MF s 1.0 D CSH (TC) MF s 1.0 D CMH (TC) MF s 1.0 D FMH (TC) MF s 1.0 D CS-MP (TC) MS s 1.0 D FS-MP (TC) MF s 1.0 D FS-MP (TC) MS s 1.0 D

Granites CSI (U) Gr ns CMI (U) Gr ls 1.0 D CS-MP (TC) Gr s 1.0 D CDP (TC) Gr s 1.0 D

Metamorphics CSI (TC) M ns CSI (U) M ns CS-MP (TC) M s 1.0 D FS-MP (G) M s 1.0 D

Alluvium Waco 5 1.2 c Al s 5 1.2 c Al w 5 1.2 c Al h s 1.2 D

s � suitable; ls less suitable; ns not suitable.

7-24


DIVERSION BANKS - SHEET 2

(i) Constructed Bank Height

H= d+ f+ s equation 7. 3

d = design depth of flow - see Table 7.6.2

f = freeboard

s = settlement (% of (d + f) depending on AMU)

(ii) Design Frequency

1 in 10.

7-25

TABLE 7. 6. Z VEPTH OF FLOW, CHANNEL WIVTH ANV CHANNEL

GRAVIENT FOR A RANGE OF PEAK FLOWS ANV RETARVANCE

CATEGORIES FOR DIVERSION BANKS

PEAK FLOW RET ARDAi'lCE GlANNEL DEP1H OF CHANNEL

(cumec) CATEGORY WID1H FLOW GRADIENT (m) (m) (%)

1.5 c 3. 0 0.5 0.4 or 0.5

D 3.0 0.5 0.4

1.5 - 2.5 c 3.0 0.6 0.4 or 0.5

D 3.0 0.6 0.4

2.5 - 3.5 c 3.0 0. 7 0.4 or 0.5

D 5.0 0.6 0.3

3.5 - 4. 5 c 3. 0 0. 8 0.4 or 0.5

D 5.0 0.7 0. 3

Constructed bank height is calculated from equation 7. 3 in section 7.4.6 for contour banks. Freeboard is increased by 10 -20% of that used for contour banks to compensate for the effect from grass growth that may occur during the summer months.

The special construction techniques required for soils normally not suitable for diversion bank construction are set out in section 7. 4. 10 for contour banks. Diversion banks on these soils should be designed with lower channel velocities. The ground under the diversion bank should be ripped before construction to ensure binding of the bank to the underlying surface.

Diversion banks require less maintenance than contour banks, as the channel is not cultivated and siltation occurs infrequently. However, maintenance is critical as failure of a diversion bank will result in contour bank failures lower down the slope.

practiced. channel.

Planting and fertilizing of the channel is generally not This would, however, provide added stability to the

7-26

7.7 SPECIFICATIONS FOR PONDAGE BANKS

Pondage banks are level diversion banks with partially closed off ends. They are designed to hold as much runoff water as possible in areas where outlets are on unstable sites or unsuitable soils.

Pondage banks are used in the Craw's Nest District to:

(i) Protect cultivation where a diversion bank outlet is not available e.g. a creek flat between a steep hill and a creek with very steep banks.

(ii) Control actively eroding gullies in pasture on unstable soils.

Soils that are not suited to contour bank construction are also unsuitable for the construction of pondage banks (see section 7.4.1) .

Ideally pondage banks should hold the total runoff of the catchment for a 1 in 10 design frequency. This is often impractical due to the excessive bank height needed. As a minimum requirement, pondage banks are designed with an additional 0 . 5 m added to the constructed bank height specifications for a diversion bank (see section 7 .6) .

Outlets can safest outlet exists. settled bank height.

be at one or both ends depending on where the The outlet should be at least 0.3 m below the

Construction and maintenance are the same as for diversion banks.

7-27

7.8 SPECIFICATIONS FOR SPREADER CHANNELS

Spreader channels are level channels, used to spread concentrated flows of runoff onto grassland.

Those soils which are not suitable for the construction of contour banks are unsuitable for the construction of spreader channels (see section 7.4.1).

Spreader channels are used for example to:

(i) Divert water away from unstable areas such as eroding waterways or creeks. In this instance, the stability further down stream of likely points of concentration of the diverted runoff should also be considered.

(ii) Spread runoff water from cultivation or natural depressions onto grassland.

Spreader channels are generally not designed. However the following construction features are recommended:

(i) Runoff water is diverted into the spreader channel by way of a contour or diversion bank. At the change over point, the channel from the contour or diversion bank is continued but the soil is pushed to the uphill side of the channel. This construction technique enables water to run out over the front edge of the spreader channel when full. Because of this construction method, the capacity of the spreader channel is less than the capacity of the contributing bank.

(ii) The gradient in the first section of the spreader channel is 0.5% gradually reducing to level over a distance of 20 - 30 m. This will assist in filling the entire channel before the water runs out. The channel should be marked out at 3 m intervals to ensure an even outflow.

(iii) The structure should be maintained to ensure an even outflow and low spots in the channel should be repaired on a regular basis.

7-28

7.9 SPECIFICATIONS FOR WATERWAYS

7.9.1 Introduction

Only a small number of waterways have been constructed in the district. In most cases runoff water is diverted into natural depressions or onto grassland. Some waterways are required across creek flats.

It is desirable to locate constructed waterways in the natural depression. If, however, the siting of the waterway in the natural depression hinders farm operations greatly or if the natural depression is badly eroded, perched waterways are used. The location of stable waterway outlets into creeks can be a problem and in such cases waterways should not be constructed.

The erosion of waterways has always been a problem in the district. The major reason for this appears to be a lack of proper establishment and maintenance of grass cover in the waterway.

Summary specifications for waterways are presented in Table 7.9.1 - summary sheets 1 and 2.

7.9.2 Suitability of Soi Is and Sites for Waterway Construction

Waterways should not be constructed on:

(i) FSI (TC), CSI (TC) , FMI (TC), CMI (TC)

due to the shallow depth of the surface A horizon overlying a very dispersible and erodible clay subsoil.

(ii) Kenmuir, BSs, BFs and Cabarlah due to the shallow soil depth to parent material.

Unless it is totally unavoidable, waterways should not be constructed on the following soils:

CSI (U), FS I (U), CMI (U) , FMI (U), CS-MH (TC), FS-MH (TC) .

If the construction of waterways can not be avoided on these unsuitable soils (e.g. to carry water from better soils above) , special construction techniques should be used (see section 7.9.9).

Soils such as CS-MP (TC) , FS-MP (TC) and soils of the Basaltic Red Soils LRA also present problems with waterway stabilisation due to the unstable and/or infertile subsoil. Special construction techniques should be used (see section 7.9.9).

Waterways should not be located in unstable or eroding depression lines.

Farming operations have also to be considered before a waterway is located (e.g. in a graingrowing area, short runs between waterways should be avoided).

7-29

TABLE 7.9.1 SUMMARY SPECIFICATIONS FOR UIATERWAYS

LRA

Basalt West

Basalt East

sasal tic Red

Soils

Marburgs

Granites

Metamorphics

Alluvium

AMU

Kenmuir

Purrawunda

BSs

BFs

BSd

BFd

BFwd

Cabarlah

Pechey

Palmtree

Geham

Ravens bourne

Pinelands 1 and 2

Merritts

CSI (TC) MF

FSI (TC) MF

CSI (U) MF

FSI (U) MF

CMI (TC) MF

CD! (TC) MF

CSH (TC) MF

CMH (TC) MF

FMH (TC) MF

cs.:.MP (TC) MS

FS-MP (TC) MF

FS-MP (TC) MS

CSI (U) Gr

CMI (U) Gr

CS-MP (TC) Gr

COP (TC) Gr

CSI (TC) M

CSI (U) M

CS-MP (TC) M

FS-MP (G) M

Waco

Al s

Al w

Al h

Kr Kikuyu runners;

Ks Kikuyu seed;

R Rhodes;

A

c

SOIL SUITABILITY

ns

s

ns

ns

s

ns

s

s

s

s

s

s

ns

ns

ns

ns

n s

s

ls

ls

ls

s

s

s

ns

ns

s

s

ns

ns

s

s

s

s

s

ls

SHEET

MAXIMUM PERMISSIBLE

VELOCITY (m/sec)

1.2

1.2

1.2

1.2

1.2

1.2

1.2

1.2

1.2

1.2

1.0

1.0

1.0

1.0

L2

1.2

1.2

LO

1.0

1.2

1.2

1.2

1.2

1.2

1.0

African star;

Indi3n bluegrass;

Creeping bluegrass;

GRASS RETARDANCE

CATEGORY

C/B

C/C

C/C

C/C

C/C or D/C

C/C or D/C

C/C or D/C

C/C

C/C

C/C

C/C or D/C

C/C or D/C

C/C or D/C

C/C or D/C

C/C

C/C or D/C

C/C or D/C

C/C or D/C

C/C or D/C

C/C or D/C

C/C or D/C

C/B

C/C or C/B

C/C or D/C

C/C or D/C

SUITABLE GRASS SPECIES

Kr, Ks, A, I

Kr, Ks, A, R, I

Kr, Ks, A, R,

Kr, Ks, A, R,

Kr, Ks, R,

Kr, Ks, R,

Kr, Ks, R,

Kr, Ks, R,

Kr, Ks, R,

Kr, Ks, R,

Kr, Ks, R,

A, R,

A, R,

A, R,

Kr, Ks, R, I

A, R, I

Kr, Ks, R, I

Kr, Ks, R,

Kr, Ks, R ,

Kr, Ks, R

Kr, Ks, R,

Kr, Ks, R,

Kr, Ks, A, I

Kr, Ks, A, R, I

Kr, �s, A, R,

Kr, Ks, A, R, I

N Normal;

T Replace top soil;

CONSTRUCTION TECHNIQUE

N

N

N

N

T

N

T

N

N

N

T

D

D

D

T

T

T

T

T

T

T

N

N

N

D

D No disturbance to channel;

TABLE 7.9.7

7-30

SUMMARY SPECIFICATIONS FOR WATERWAYS

SHEET Z

(i) Waterway Type

Trapezoidal with flat bottom because trickle flow s do not occur in the district.

(ii) Design Frequency

(iii)

(a) 1 in 10 for waterways in natural drainage lines

(b) 1 in 50 for perched waterways

(c) Reduce the design frequency for very large waterways.

Constructed Bank Height

H = d + f + s

d = design depth of flow

f = freeboard

s = settlement (% of (d + f) depending on the AMU).

(iv) Stabilisation

(a) Establish suitable grass species

(b) Fertilize

(c) Keep runoff water out of waterway until 60% grass cover

(d) Careful selection of waterway outlet into the creek.

(v) Maintenance

(a) Fertilize and slash on a regular basis

(b) Permanent fencing to exclude cattle

(c) Repair any structural damage immediately.

7-31

7.9.3 Waterway Channe I Shape

Trapezoidal or parabolic waterways are both stable, but in small runoff events water will tend to meander more in waterways with a flat bottom. In the Crow's Nest District, where trickle flows do not occur frequently, waterways with a flat bottom are suitable. Waterways with a flat bottom are easy to construct but require careful checking after construction to ensure a minimum side slope.

Waterway bank batters should be 3 in 1 in grain and grazing areas and in small crop areas should be 4 in 1 to facilitate crossing with farm implements.

For small catchments in small crop areas the table drain of the farm road can be designed as a waterway. These are constructed with a triangular cross section with side slopes not exceeding 1 in 1. The actual farm track may be used as a waterway if it is surfaced with non erodible material such as concrete.

In grain and grazing areas, the proportion of the depth of flow below ground level is highly variable. In small crop areas, waterways should be constructed completely below the surface so that runoff from the furrows and banks can flow readily into the waterway. Farm drainage will be improved by subsurface waterways.

7.9.4 Design Frequency

(i) Natw>al Depressions

Most natural depressions in the Crow's Nest District are very deep with capacities exceeding the 1 in 100 design frequency and generally detailed design is not required. However, in shallow depressions a bottom width should be left in grass to handle the 1 in 10 design frequency. Outlets should be grassed and stabilised before contour banks are discharged into natural depressions.

(ii) Constvueted Wate�ays

Waterways are designed for a 1 in 10 return period with the following exceptions:

(a) Perched waterways (located away from the natural depression) are designed for a 1 in 50 return period, because of the potential for damage to the contour bank system when a waterway bank breaks through.

(b) For larger catchments where the 1 in 10 bottom width exceeds 30 metres, it may be possible to:

reduce the return period or

design a maximum waterway width.

7-32

For waterways designed with either a reduced return period or a maximum width, the design velocity should not exceed 1.2 m/sec and the landholder should be consulted on the increased risk of failure.

7.9.5 Vegetal Retardance Categories

Vegetal retardance categories are determined by measuring the height and density of the grass cover.. Therefore these categories vary with the growth of the sward. When the waterway design is based on a certain category, the growth of the cover has to be up to that standard to provide an effective protection against waterflow.

(i) Grain and Grazing Areas

(a)

(b)

Soils with a moderate fertility status or a low erodibility.

Soils with a high fertility status especially in drainage lines with a better than average grass growth in summer.

(c) Soils with low fertility status:

With fertilization

Without fertilization (expected that the landholder will not maintain grass growth)

Retardance C for velocity and capacity.

Retardance C for velocity and retardance B for capacity.


Retardance D for velocity and retardance C for capacity.

(ii) Small Crop Areas (better grass growth due to irrigation and fertilization of the erop)

(a)

(b)

Waterways crossed by traffic.

Waterways not crossed by traffic.


Retardance B for velocity and capacity.

Vegetal retardance categories can be determined in the field with the use of the Modified Ellinbank Pasture Meter (EPM) or drop board (Truong, 1979).

7-33

7.9.6 Maximum Permissible Velocity

Maximum permissible velocities vary with vegetal retardance, and soil erodibility.

( i) Grcr:in and Grazing Areas *

(a)

(b)

(ii)

7. 9. 7

Stable soils

Unstable soils

Small Crop Areas

Design Depth of Flow

1.2 m/sec

1.0 m/sec

2. 2 m/sec.

The design depth of flow and bottom width for the l in 10 design frequency are presented in Appendix X and XI for grain and grazing areas. The design depth of flow for the l in 10 design frequency, a retardance value of C and a maximum permissible velocity of 2.2 m/sec are presented in Appendix XII for table drain and trapezoidal waterways in small crop areas.

7.9.8 Constructed Bank Height

Constructed bank height is determined from the equation:

H = d+ f+ s equation 7. 3

where H constructed bank height (m) d = design depth of flow (m) f = freeboard (m) s = allowance for settlement % of (d + f)

Freeboard of 0.15 m is added to allow for small changes in the bed slope and standing waves that can occur at curves in the waterway. Freeboard is not added for waterways in small crop areas as the waterway runs straight down the hill.

The allowance for settlement is tabulated in Table 7.4.4. Settlement is not required for sub surface waterways.

7.9.9 Waterway Construction

Waterway construction techniques are explained in an advisory leaflet (Lehmann and Bartels, l978b).

Dozers and graders have both been used successfully for the construction of waterways. Generally a dozer is preferred for large waterways and a grader for very small waterways.

The specifications of the waterway, especially the cross section should be checked after construction. In waterways with a flat bottom the side slope should not exceed 0.2%. It is especially important to check the side slopes of the bottom of perched waterways cut into the side of the hill.

* �ese yelocities for the g!ain and grazing areas are lower than those g1ven 1n the Queensland So1l Conservation Handbook. However by adding 0.15 m freeboard, velocities will be.close to those in the Handbook when the waterway runs at full capac1ty.

7-34

On those soils where the existing natural grass cover should not be disturbed during construction (see section 7.9.2), waterways should be designed with a very wide bottom and with banks no higher than 10 em - just enough to keep the water in the channel. The banks should be constructed from the outside, leaving the waterway bottom undisturbed. The subsequent channel on the outside of the waterway should be blocked off every 25 m.

For those soils where the topsoil should be replaced during construction (see section 7.9.2) , waterways should be constructed in sections in the following manner:

and

(i) Push the topsoil onto a lower section.

(ii) Construct the waterway bank with the subsoil.

(iii) Push the topsoil back into the waterway channel.

7.9. 10 Grassing of Waterways

(i) Grass Species

Rhodes grass and kikuyu are the two main species currently used and accepted by the local farmers. Rhodes grass is more popular as it can be easily established from seed.

In addition to these two species, African star grass, and Indian bluegrass have shown promise in other districts of comparable climatic and soil conditions and could be tried out in the Crow's Nest District. Suitable grass species for the AMUs are listed in Table 7.9.2.

KikUYU

This species is currently being used in all LRAs. However, due to its high moisture and fertility requirements, it is less suitable for the coarse textured surface soils of the Granites, Metamorphics and Marburgs LRAs.

In the past, Kikuyu has been planted from runners. This method is time consuming and even under favourable weather conditions takes a long time to provide an adequate cover. Two seeded strains are now commercially available (Whittet and Breakwell), but have not been used in the district.

Whittet tends to clump if allowed to grow unchecked. It should be kept fairly short with either grazing or slashing. Germination can be a problem and initial growth is slow.

Breakwell is ground hugging but areas with a rainfall in excess of 900 mm and in parts of climatic zones Al and B. problem.

is susceptible to rust in - i.e. in climatic zone A2 Germination can be a

To maintain a good cover of kikuyu, annual fertilizing is essential especially on the less fertile soils. Maintenance fertilizer should be applied early in spring to reduce winter weeds through increased competition from the grass.

7-35

TABLE 7.9.2 SUITABLE WATERWAY GRASS SPECIES FOR THE AML/6

LRA

Basalt West

Basalt East

Basaltic Red Soils

Marburgs

Granites

Metamorphics

Alluvium

Kr = Kikuyu runners; Ks = Kikuyu seed;

AV.U GRASS SPECIES

Kenmuir Purrawunda Kr, Ks, A, I

BSs ) BFs ) BSd ) Kr, Ks, A, R, I BFd ) BFwd )

Cabarlah ) Pechey ) Palmtree ) Geham ) Kr, Ks, R, I Ravens bourne ) Pine 1 ands 1 and 2 ) Merritts )

CSI (TC) MF FS I (TC) MF csi (U) MF FSI (U) MF CMI (TC) MF CDI (TC) MF A, R, I CSH (TC) MF CMH (TC) MF FMH (TC) MF CS-MP (TC) MS FS-MP (TC) MF FS-MP (TC) MS

CSI (U) Gr CMI (U) Gr CS-MP (TC) Gr CDP (TC) Gr

CSI (TC) M CS I (U) M CS-MP (TC) M FS-MP (G) M

Waco Al s Al w Al h

A • African star grass; R = Rhodes grass; I = Indian bluegrass;

A, R, I A, R, I Kr, Ks, R, A, R, I Kr, Ks, R, Kr, Ks, R,

Kr, Ks, R, Kr, Ks, R,

Kr, Ks, R, Kr, Ks, R,

Kr, Ks, A, Kr, Ks, A, Kr, Ks, A, Kr, Ks, A,

I

I I

I I

I I

I I R, R,

I I

7-36

Rhodes Grass

Although Rhodes grass does not provide a very good surface cover it is most popular as it can be established from seed and often establishes naturally from surrounding areas.

Rhodes grass can be planted either by itself or in combination with Indian bluegrass. It is suitable for all LRAs and climatic zones. Although its fertilizer requirement is lower than kikuyu, a maintenance programme is required to maintain an effective cover.

Pioneer and Callide are the most commonly used strains in the district. As these two cultivars are tufted, the better spreading cultivar Katambora is recommended if seed can be obtained.

African Star Grass

This grass can provide an excellent cover when properly established. It is ground hugging and very drought resistant. It can spread quickly under good moisture conditions, but has to be planted by runners as seed viability is extremely low.

African star grass can become a weed in cultivation in high rainfall areas especially on the lighter textured soils. Therefore it is not recommended for areas where annual rainfall exceeds 850 mm. On the other hand it provides a very good cover on waterways on the loamy textured soils of the Marburgs LRA where cultivation is not anticipated.

African star grass will colonize gullied areas better than kikuyu and is therefore more suitable in rehabilitation of eroded waterways.

Indian �lue Grass

This grass possesses most of the desirable characteristics of a waterway grass. It can be sown from seed and thrives on soils ranging from heavy clays to sandy loams. It is very drought tolerant. It is fairly sensitive to frost which kills most top growth but the ground layer will grow again in spring when moisture is available.

It can be successfully established in south east Queensland and an adequate cover can be obtained 12 months after sowing.

Weed control in the first two years is essential in the establishment of this species.

(ii} Grass Establishment

A deep and fine seedbed can cause serious erosion in a waterway, even when contour banks do not discharge into it. A firm and shallow seedbed is recommended to reduce soil loss. A reasonably good seedbed can be prepared with minimum soil disturbance on sandy surfaced soils and the soils of the Basaltic Red Soils LRA. Establishment is more difficult on cracking clays and hard setting loams where rolling is essential at sowing.

7-37

All grasses can be broadcast together with fertilizer and rolled in. If summer weeds are a problem, pre-emergent herbicides should be used.

Seeding rates should be at least 2 or 3 times the normal rates recommended for pasture production. Planting time varies with the area but normally the period between November and February is recommended.

In the first few years, weed control is often needed to promote the sown species. Strategic use of herbicides and/or slashing will provide effective control.

Research work in other districts indicates that a cover crop of oats or barley planted in autumn or millets in early spring may aid grass establishment in the summer. The cover crop protects the waterway surface against high intensity storms in early summer and also provides mulch for grass establishment. To reduce moisture and light competition the cover crop should be sprayed with non selective herbicides such as Round Up prior to sowing of the grass. Seed and fertilizer are broadcast into the dead mulch and rolled in with tractor tyres. Weed control is normally needed during the first two years to ensure a satisfactory grass cover by reducing weed competition.

(iii) Fertilizer Requirements

To discourage weed growth, fertilizer rates are kept to the minimum level at planting. Therefore, follow up applications are essential. The recommended rates are as follows:

LRA

Basalt West

Basalt East

ESTABLISHMENT (kg/ha)

Urea - 80

( Urea - 80 ( Superphosphate - 100

MAINTENANCE kg/ha/year

Urea - 50

Urea - 50

Basaltic Red Soils, Marburgs and Metamorphics

( N.P.K. - 100 ( (approx. 10.10.10 ( Urea - 50

Urea - 50 Superphosphate - 50

Alluvium (except Waco) N. P.K. - 50 Urea - 50

7.9.11 Waterway Stab i I i ty

Most damage to waterways occurs in the first 2 years before adequate grass cover is established. This damage can be decreased by:

(i) Not letting runoff water into the waterway until at least 60% ground cover has been achieved -even if this takes 3 years. When the ground cover is about 40%, the top contour banks are allowed to empty into the waterway to provide additional moisture for grass growth. The remainder of the banks are connected to the waterway once the ground cover exceeds 60%.

(ii)

(iii)

(iv)

(v)

(vi)

(vii)

(viii)

(ix)

7-38

Adhering strictly to waterway specifications in this chapter and checking that construction standards meet these specifications.

Considering soil stability before selecting the site (section 7.9.2).

Grassing and fertilizing the waterway as recommended in section 7.9.10.

Using permanent pasture as a disposal area wherever possible or constructing the waterway banks from the outside before a pasture is broken up.

Careful selection and grassing of the waterway outlet into the creek. Most creeks in the district have steep banks and stable outlets are not always easy to find. In extreme cases, on unstable soils, grass strips should replace a contour bank/waterway system.

On highly erodible soils, surface stabilizers such as Holdgro or Enviromat should be used to provide extra protection at contour bank outlets.

Temporary fencing of waterways to keep cattle out.

Not using the waterway as a convenient access track.

7.9.12 Maintenance of Waterways

Fertilizing and slashing should be undertaken on a regular basis. Slashing is particularly important in small crop areas where regular irrigation and fertilization of crops can produce excessive grass growth which can block the flow of water.

On deep, cracking clay soils on steep slopes, invasion by Queensland bluegrass could make waterways less stable. Kikuyu, especially, requires high levels of nitrogen to compete against other grasses.

Established, stable waterways can fail if overgrazed. Permanent fencing to exclude stock is recommended especially for critical areas, such as steep eJreekbanks at the outlet of the waterway.

The waterway should not be used as a convenient access track. Adequate precautions should be taken during the planning stages to prevent this happening. In the case of small crop farms, concrete tracks should be constructed if waterways are used for access.

All structural damage should be repaired immediately.

7-39

7.10 SPECIFICATIONS FOR GRASS STRIPS

There are two types of grass strips:

(i) Narrow grass strips approximately 10 m wide.

(ii) Wide grass strips which occupy approximately SO% of the potentially cultivatable area.

Grass strips are used where stable contour bank outlets are not available or on those soils suitable for cultivation but not for bank construction i.e. FMI (TC) and CM I (TC) .

Grass strips are an inexpensive alternative to contour banks for areas of temporary cultivation which are to be established to improved pasture or to tree crops where a sod cover will be maintained between the trees.

The vertical interval from the centre of one grass strip to the next is based on the equation:

where

V I = 0.15 (s + x) - see Equation 7.1

VI = vertical interval between the centre of each grass strip (m)

s = land slope (%)

x =drainage design rating for the AMU (see Table 7.4.2)

For all crops, in erosion hazard zones 1 and 2 (see chapter 9) , 10 m wide grass strips are used, whereas in zone 3 the strips should occupy 50% of the area.

Grass strips should not be used in permanent cultivation as the only control measure on long slopes where runoff water will concentrate. Any concentration of water will require cross slope drainage.

Native grasses are adequate in the strips. However if strips are surveyed after the paddock has been broken up, improved pasture species should be planted. Recommended improved pasture species are listed for each AMU in chapter 1 1 and Appendix XIV. Normal cultural practices to maintain pasture growth should be observed.

7-40

7.11 SPECIFICATIONS FOR PASTURE FURROHS

Pasture furrows are small level banks, spaced at approximately 3 to 8 m intervals.

Pasture furrows will reduce runoff and assist in reducing soil erosion in pastures. The ponding of water and the subsequent increased water intake will benefit pasture growth.

Pasture furrows are not recommended to improve pasture production in the Grow's Nest District. Although pasture furrows have been used with success in areas west of Miles to promote pasture growth, the cost/benefit ratio in the Grow's Nest District with a more reliable rainfall is doubtful.

Pasture furrows have been used on a trial basis to revegetate scalded eroding areas in the Grow's Nest District.

Pasture furrows have a shallow channel and can be used on all AMUs apart from the GSI (TG) and FSI (TG) .

Pasture furrows are generally not designed and the distance between the furrows is determined by economic considerations. To be effective, pasture furrows should not be more than 3 to 8 m apart, depending on the land slope and AMU.

Pasture furrows are constructed either with an uphill push or a downhill push. A pasture furrow with a channel on the downhill side will give maximum benefit to the pasture, whereas a channel on the uphill side will give maximum runoff control.

A grader or a dozer with hydraulic control of the blade angle is preferred for the construction of pasture furrows.

8- 1

8. AGRONOMIC PRACTICES FOR EROSION CONTROL

8.1 INTRODUCTION

While runoff control structures will prevent major scouring they will not significantly reduce runoff nor will they adequately reduce soil erosion. Agronomic practices that will increase water infiltration and reduce soil detachment are required to reduce soil losses to acceptable levels.

Recommended agronomic practices for the Crow's Nest District are defined.

8.2 GRAIN AND FODDER CROPS

The majority of the cultivated land in the district is on land slopes between 5 and 12%. The current agronomic practices which involve the grazing of both fodder crops and grain crop stubble predispose this area to soil erosion on these land slopes. Alternative agronomic control practices are needed to reduce soil loss to acceptable levels.

Alternative practices which are recommended include:

(i) Retain crop stubble either on the soil surface or at least through incorporation. However, under the current farming system where each farmer only grows small areas of grain to support animals, the use of machinery to retain stubble and the use of chemicals to control weeds are not considered to be viable alternatives.

(ii) Delay the first cultivation to a time as close as possible to planting. This provides a surface that has been compacted and possibly roughed up by animals and with some stubble litter protection.

(iii) Practice opportunity cropping. Cowpeas and millets are suitable crops.

(iv) Sod seed fodder crops directly into pasture. Sod seeding machinery instead of the currently used combine planters will be required. There are still some technical and economic problems associated with this technique. These include competition from winter weeds towards winter crops and a lack of soil nitrification with minimum tillage operations. This latter problem may be overcome by using legumes in fodder crops and nitrogenous fertilizers in grain crops.

8-2

In addition to oats, summer legumes such as Dolichos lab lab have been sod seeded. Winter legumes such as woolly pod vetch are an alternative that should be tested.

In early trial work on sod seeding in the Craw's Nest District, germination and production were reduced significantly with less than two workings into pasture.

(v) Use summer fodder crops such as Dolichos lab lab which is an early crop with a long growing season.

(vi) Use other land use options and reduce the area required for winter fodder crops by

(a) Planting the area to improved pasture.

(b) Planting winter grasses (fescue and phalaris) and legumes (clover and medics) into existing improved or native pasture.

(c) Planting small areas of irrigated pasture of lucerne or rye grass instead of forage crops. Water requirements for rye erass are higher than tor lucerne but lucerne is not a good winter pasture.

(d) Using crop and pasture rotations. The problems associated with crop and pasture rotations and improved pastures include:

difficulties in establishing pasture in areas of unreliable rainfall (climatic zones B and C) ;

the productivity of winter pastures is low and unreliable in climatic zones B and C. Fodder crops are therefore the best alternative;

improved pastures require high inputs of fertilizer on the poorer soils.

Improved pastures are therefore seen as likely alternatives to grazing crops in:

climatic zones Al and A2; and

on those AMUs which have at least either a moderate nutrient status or moderate plant available water capacity.

8-3

8.3 HORTICULTURAL CROPS

(i) Small C�ps

Management practices which will reduce soil loss include:

(a) Fast growing cover crops such as millets or cowpeas in situations where small crops are not grown continuously. Such crops will provide cover during the growth cycle and subsequently stubble benefits.

(b) Use seedling pots to plant well advanced seedlings into the field and so reach maximum cover protection much earlier. In addition, the use of seedling pots reduces the need for a fine and firm seedbed. Seedling pots are not suitable for all small crops e.g. carrots.

(c) Maintain the soil in a rough condition whenever possible.

(d) Use measures to both maintain surface soil stability and to improve soil nutrient status.

(ii) Tree and Vine Crops

Sod cover should be maintained between tree and vine crops. This cover should also be maintained during the establishment period.

The high and reliable rainfall in climatic zones Al and A2 are favourable for the growth of sod cover.

8.4 PASTURES

Management practices should be undertaken to maintain adequate ground cover and prevent the concentration of surface runoff. Such practices include:

(i)

(ii)

(iii)

(iv)

Establishment of sown pastures in suitable climatic zones on suitable AMUs. Details of recommended species and fertilizers are set out in chapters 6 and 11.

Regulation of stocking rates. A ground cover of 75% with an average pasture height of 15 to 25 mm

is desirable. Runoff increases rapidly when ground cover drops below 75%. Carrying capacities are presented in chapter 6. On unstable soils such as CSI (TC) and FSI (TC) pastures should be grazed after rain and then destocked.

Follow the grazing management practices outlined in chapter 6.

Select stock watering points carefully to avoid stock tracks concentrating runoff water and causing soil erosion.

9-1

9. CONSERVATION MANAGEMENT SYSTEMS

9.1 INTRODUCTION

The majority of cultivated land is on land slopes between 5 and 12 % and is used predominantly for fodder cropping of oats and grain cropping of barley. This combination of land slope and crops in association with the rainfall erosivity and seasonal distribution (Figure 2.1) predisposes the area to a serious erosion problem. The soil must therefore be protected with conservation management systems which both control and reduce runoff and reduce soil loss.

Conservation management systems involve combinations of runoff control structures (to control runoff - see Chapter 7) and agronomic practices (to reduce runoff and soil loss - see Chapter 8) . Conservation management systems have been designed to reduce soil loss to acceptable levels and so maintain the long term productivity of the land. The level of protection must be increased as the land slope steepens.

9.2 GRAIN AND FODDER CROPPING

Interim conservation management systems (based on current land use and levels of management) for erosion hazard zones 1 to 4 are presented in Table 9.1. The slope limits for each AMU for the erosion hazard zones are presented in Table 9 . 2 . The slope limits for the various soils are governed by soil erodibility which is presented in Table 9. 3.

Areas that exceed the slope limits of zone 3 should be returned to native or improved pasture. In some cases, sod seeding of fodder crops into pasture with the use of contour banks may be an acceptable alternative. Grass strips must replace contour banks where suitable outlets are unavailable.

Eroded phases should be treated as the normal phase in the next highest land slope category. For example an eroded phase with the land slope of erosion hazard zone 1 should be treated with erosion hazard zone 2 specifications. Eroded cultivated land that is classified as zone 4a should be returned to pasture and the rehabilitation measures in Chapter 10 should be undertaken.

TABLE 9.1

9-2

INTERIM CONSERVATION MANAGEMENT SYSTEMS FOR THE EROSION HAZARD

ZONES FOR VRYLANV GRAIN ANV FOVVER CROPPING

LAND USE ZONE 0 ZONE 1 ZONE 2 ZONE 3 ZONE 4a AND 4b**

Grain cropping +

N DSCB/SI or DSCB/SM or SSCB/SM SSCB SSCB/SI

Fodder cropping N SSCB or SSCB/MT or SSCB/SS or 10% pasture/ 30% pasture/ GR (50%)* or DSCB SSCB 50% pasture/

SSCB

Fodder cropping/ N SSCB SSCB/SI SSCB/SM Grain cropping (grain) and (grain) and

MT (fodder) MT (fodder) (fodder cropping should not exceed 3 in 10 years)

N = no special conservation management required; NR = not recommended.

DSCB double standard spaced contour banks; SSCB standard spaced contour banks;

SI stubble incorporation; SM stubble mulch; MT minimum tillage; SS sod seeding;

GR (SO%) = grass strips SO% of area.

(i) (ii)

NR NR

SSCB/SS NR

NR NR

* Treatment if soils are not suitable for the construction of contour banks.

** Erosion hazard zones 4a/4b have been divided into:

(i) areas where no timber restrictions apply

+

(ii) areas where timber restrictions apply.

Grain crops include barley, wheat, early sorghum, millets and panic�. Crops such as soybeans and sunflowers require the same management levels as fodder crops.

TABLE 9.2

9-3

SLOPE LIMITS FOR THE EROSION HAZARD

ZONES FOR THE AMUI

LAND SLOPE LIMITS (%) LRA AMU

ZONE 1 ZONE 2 ZONE

Basalt West Kenmuir NS NS NS Purrawunda 3 5 8

Basalt East BSs NS NS NS BFs NS NS NS BSd 3 5 8 BFd 3 5 8 BFwd 3 5 8

Basaltic Red Cabarlah NS NS NS Soils Pechey 3 5 8

Geham 3 5 8 Merritts 3 5 8 Ravens bourne 4 6 10 Pinelands 1 and 2 4 6 10 Palm tree 4 6 10

Marburgs, CSI (TC) NS NS NS Metamorphics CSI (U) NS NS NS and FSI (TC) NS NS NS Granites FSI (U) NS NS NS

CMI (TC) 2 FMI (TC) 2 CMI (U) 3 FMI (U) 3 CSH (TC) 3 5 8 CMH (TC) 3 5 8 FMH (TC) 3 5 8 CS-MP (TC) 3 5 8 FS-MP (TC) 3 5 8 FS-I'P (G) 4 6 10 CDl (TC) 4 6 10 C:JP (TC) 4 6 10

NS ; Not suitable for permanent cultivation.

3

TABLE 9. 3

LRA

Basalt West

Basalt East

Basaltic Red Soils

Marburgs

Granites

Metamorphics

9-4

EROVIBILITV FACTORS (K FACTOR)

FOR THE AMU6

SOIL EROD IBILITY

AMU (K factor after Wischmeier and

Smith, 197 8)

Kenmuir 0.26 Purrawunda 0.38

BSs 0.26 BPs 0.26 BSd 0. 36 BPd 0.38 BFwd 0.38

Cabarlah 0.26 Pechey 0.26 Palmtree 0.24 Geham 0.26 Ravens bourne 0.24 Pinel ands 1 and 2 0. 24 Merritts 0.36

CSI (TC) MF 0.42 PSI (TC) MF 0.45 CSI (U) MF 0. 25 PSI (U) MF 0. 31 CMI (TC) MP 0.37 CDI (TC) MF 0. 31 CSH (TC) MP 0.37 CMH (TC) MP 0.37 FMH (TC) MP 0.37 CS-MP (TC) MS 0.28 PS-MP (TC) MF 0.28 PS-MP (TC) MS 0. 28

CSI (U) Gr 0.25 CM I (U) Gr 0.21 CS-MP (TC) Gr 0.24 CDP (TC) Gr 0.18

CSI (TC) M 0.42 CSI (U) M 0.25 CS-MP (TC) M 0.28 FS-MP (G) M 0. 25

9-5

9.3 HORTICULTURAL CROPS (Tentative specifications only)

of:

9. 3 .. 1 Small Crops

Erosion on small crops can be controlled by a combination

(i) A system of runoff control structures. These can be modified contour banks/beds or normal contour banks or parallel contour banks at double* standard bank spacings.

(ii) Agronomic practices in Section 8.2.3.

The land slope limits for soils for the erosion hazard zones for grain cropping should be observed.

9.3.2 Tree and Vine Crops

The normal practice is to keep a sod cover between the rows. When a good sod cover is maintained, soil conservation measures or contour planting is not required. When temporary cultivation is necessary prior to planting, it is recommended to use grass strips. Grass strips will not interfere with the tree or trellis layout.

The tree clearing land slope limits (Table 9.4) for the AMUs should not be exceeded for the establishment of tree and vine crops.

9.4 PASTURES

Management of pasture to prevent soil erosion involves:

(i) The use of sound agronomic practices, and

(ii) The observance of tree clearing limits.

Runoff control structures are not an economic proposition and if sound agronomic management is practised are not required. Pasture furrows and contour ripping as indicated in Chapter 7 will be advantageous in some situations. Contour banks or grass strips should be used if land is cultivated for a considerable period for the establishment of improved pastures.

( i J Agronomic

The agronomic management practices for production 6) and for erosion control (Chapter 8) should be observed. particular overgrazing should be avoided.

(Chapter In

* Double standard spacings will result in higher channel velocities than with single spacing. This does not matter as the channels are grassed.

9-6

(ii) Tree Clearing Limits

Recommended tree clearing restrictions are set out in Table 9.4 for those soils with impermeable sub soils of the Marburgs, Granites and Metamorphics LRAs. For all other AMUs, the cost of development, the control of woody weed regrowth and the control of soil erosion become limiting factors to development on land slopes in excess of 17 to 20%. In addition, trees on higher land slopes offer watershed protection and long term protection against the possibility of soil salinity in low lying areas.

TABLE 9.4 RECOMMENDED UPPER LAND SLOPE LIMITS FOR

TREE CLEARING FOR THE HIGHLY ERODIBLE SOILS OF THE

MARBURGS LRA IN THE CROW'S NEST DISTRICT

AMU UPPER LAND SLOPE LIMIT (%)

CSI (TC) 4

CSI (U) 7

FSI (TC) 4

FSI (U) t

CMI (TC) 4

CMI (U) 7

FMI (TC) 4

CMI (U) 7

10-1

10. SPECIFICATIONS FOR SPECIAL PURPOSE LAND USE

10.1 SPECIFICATIONS FOR SUBDIVISION AND FARM AMALGAMATION

10.1.1 Introduction

district. Subdivision and farm amalgamation are undertaken in the

Subdivision falls basically into three categories:

(i) Subdivision of a large property into smaller farms.

(ii) Subdivision of land into semi-rural land for hobby farms.

(iii) Subdivision of land into residential blocks with a maximum size of one hectare.

There is a great interest in subdivision for semi-rural and residential land, mainly in the Toowoomba - Geham - Meringandan area. This area is close to Toowoomba, has a mild climate with a reliable rainfall, an aesthetically pleasing landscape and town water available to many localities.

Both subdivision of large properties into smaller, mostly non viable farms and farm amalgamation occur on a limited scale. Amalgamation, especially in the Djuan - Douglas area, of small dairy farms is desirable, but is hampered by high land prices.

10.1.2 General Procedures for Subdivision

In the Crew's Nest Shire, plans for all subdivisions are referred by the Local Authority to the Soil Conservation Branch for comment.

In all subdivisions, whether rural, semi-rural or residential, runoff disposal has to be integrated with runoff disposal from the surrounding farming land. The Local Authority liaises with Soil Conservation Branch to determine entry and exit points of runoff disposal schemes of the surrounding rural land.

Runoff disposal in semi-rural and rural subdivisions are generally designed by the Soil Conservation Branch. Boundaries of properties within subdivisioil3for rural and semi-rural land should be located to suit a soil conservation drainage layout. The design for the stormwater disposal within residential subdivisions is generally performed by the Local Authority.

10-2

10.1.3 Recommendations for Semi-Rural Subdivision (Hobby Farms)

Semi-rural subdivisions can result in a more intensive land use and increased runoff (more buildings, yards, grain and fodder cropping, orchards, small crops, intensive grazing) . The upper limits for the AMUs (based on the upper slope limits for clearing) for semirural subdivisions are indicated in Table 10.1

TABLE 10 • 1 SUITABILITY OF THE AMUI FOR

SEMI-RURAL SUBDIVISION

LAND SLOPE (%)

AMU NOT LIHITED SUITABLE

SUITABLE SUITABILITY

CSI (TC and U) , FSI (TC and U) All slopes

CMI (TC) , FMI (TC) > 4 < 4

CMI (U) , FMI (U) > 7 < 7

FDI (U) , CS-MH (TC) > 17 8 - 17 < 8

FS-MH (TC) , CS-MP (TC) >17 8 - 17 < 8

FSP (TC) , FMP (TC) >17 8 - 17 < 8

FOP (U) >17 8 - 17 < 8

CDI (TC) , CDI (U) >17 10 - 17 < 8

CS-MP (G) , FS-MP (G) >17 10 - 17 < 8

All other AMUs >17 <17

The shallow effective soil depth, low productivity and high soil erodibility limits the suitability of CSI (TC and U) , FSI (TC and U), CMI (TC) , FMI (TC) , CMI (U) and FMI (U) for subdivision.

Land with > 17% land slope is generally not suitable for intensive land use, road construction, dam construction, etc.

Land with limited suitability can be subdivided provided it is not used for permanent cultivation for small crops and for grain and fodder cropping.

10-3

10.1 .4 Subdivision for Residential Land

CSI (TC) and FSI (TC) should not be used for subdivision and CSI (U) and FSI (U) should be avoided. These AMUs have an effective soil depth of less than 15 em - the first two AMUs with dispersible subsoils and the latter two over rock. Septic tanks are a problem. on these soils, and have to be emptied once a week. They are poor garden soils because of their shallow depth and in low lying areas drainage problems occur. CSI (TC) and FSI (TC) have extemely erodible B horizons and would require kerbs, channels and underground drains. Stormwater outlets will erode severely on sloping land, while on low land slopes drainage is a serious problem. CMI (TC) and FMI (TC) also have dispersible subsoils (similar to those of CSI (TC) and FSI (TC) ) but because of the deeper A horizon (up to 30 em) can be used for subdivision. However they should be avoided if possible.

10.2 SPECIFICATIONS FOR REHABILITATION OF TOPSOIL QUARRIES

Disused topsoil quarries in the district have not been rehabilitated. These abandoned quarries may result in loss of productivity, increased runoff, increased erosion and release of soluble salts into the runoff water. Many of these quarries have stabilized with woody weed regrowth without rehabilitation.

Land abandoned after quarrying should be restored in such a way that the area does not present an erosion risk. Rehabilitation work would normally consist of fencing and destocking. Fertilising to promote grass growth is recommended. It may be necessary to sow pastures or to install some runoff control structures, where increased runoff presents an erosion risk to lower lying areas.

Soils with dispersible subsoils should not be quarried unless a complete reshaping and restoring of surface A horizon is carried out. Because of the high cost of these operations, the sandy shallow surfaced texture contrast soils are not suitable for topsoil quarrying.

The co-operation of the Shire Council is essential to achieve rehabilitation of quarries.

10.3 SPECIFICATIONS FOR RECLAMATION OF SEVERELY ERODED LAND

10.3.1 Introduction

The conservation management systems as indicated in Chapter 9 will prevent serious soil erosion on non eroded land. If the area is already eroded, the following measures should be undertaken to stabilize the area. These measures will in general not return the area to its original condition.

10-4

10.3. 2 Severely Eroded Cultivated Land

The following procedures are recommended:

(i)

(ii)

(iii)

(iv)

Gullies should be filled if economically possible. If this is not feasible the area should be removed permanently from cultivation and treated as eroded pasture land (see Section 10.3.3) .

Runoff control structures should be installed (contour banks, waterways) as set out in the specifications in Chapter 7. Contour banks should not be constructed until grass is successfully established in the waterway.

The paddock should be removed from commercial crop production for at least four years and planted to grass or lucerne. If the land slope exceeds the acceptable limits for eroded cultivation, the paddock should be permanently removed from cultivation.

When the area is returned to crop production, the management levels for eroded phases in Chapter 9 should be observed.

10.3.3 Severely Eroded Pasture Land

The following procedures are recommended:

(i) Reduce the stocking rate to at least one quarter of the recommended stocking rate (see Chapter 6).

(ii) Plant suitable pasture species (Chapter 6 and 11) and fertilize at double the recommended rate. for pastures. Fertilizer application will be uneconomic but will increase ground cover.

(iii) The land slope limits for tree clearing in Table 9.4 should be observed. Tree planting should be considered for very steep land slopes that have been cleared.

(iv) Woody regrowth should be controlled either by slashing or with chemical treatment rather than by bulldozing or burning.

(v) Runoff water should be dispersed and not concentrated. Pondage banks, pasture furrows or pasture ripping should be undertaken to retain water. Pasture furrows and pasture ripping are not effective if the area has severe gully erosion.

(vi)

(vii)

(viii)

10-5

Treat eroded gullies and creek lines as indicated in Section 10.3.4.

Scalded areas should be contour ripped to increase infiltration and/or cultivated to establish pastures.

After reclamation observe the management recommendations made in this manual.

10.3.4 Eroded Gul I ies, Creeks and Waterways

The cause should be identified and rectified e.g.

(i) Cattle tracks to a watering point in a creek.

(ii) Unstable outlet area for a runoff control structure.

If this does not control the problem the following measures are recommended:

(i)

(ii)

(iii)

(iv)

(v)

The damaged area should be fenced and destocked.

Suitable grass species (African star, creeping blue grass) should be planted and fertilized at double the recommended rate for pastures. The grass should be watered if possible.

Reshaping is generally not recommended as there is a high risk that loose soil material will be washed away before grass can be established. However small pot holes and depressions should be filled with a soil/grass mixture.

In addition t'lte followine measures may be required:

Concentrated flows of runoff water should be temporarily diverted to more stable areas. It should be ensured that this diverted water does not cause damage elsewhere. Contour banks should be used to divert the water if stable outlets are available and pondage banks where stable outlets are not available. Pasture furrows may be adequate if the gullies are small.

Construct gully runoff control structures where appropriate.

(a) Non dispersible subsoils and gullies < 2 m deep.

Gabian Weirs - used to stabilize very large waterways; expensive and is mainly used on works of general benefit.

Loose Stone Weirs - successful on small catchments; construction is labour intensive.

Rock filling - requires large amounts of stone.

*

10-6

(b) Dispersible subsoils and very deep gullies (> 2 m) •

Masonry or Sand Bag or Rock Flumes* -used to dissipate excess energy produced by a rapid change in stream base level which occurs at gully overfalls; suitable for immediate use; conve� a large discharge through a small width; high labour and/or high material costs (J. Marshall, pers. comm.).

The success of the structure is dependent on ensuring that the energy developed by water falling over the gully head is fully dissipated in the stilling basin at the toe of the chute. In addition, the stream gradient downstream of the structure must be considered when determining the level of the stilling basin. Sidewalls must be fully protected to prevent water from high flows splashing down behind the structure. Toewalls must be inserted to prevent flows undermining the structure.

11-1

11. SUt1MARY OF MANAGEMENT PRACTICES

FOR THE AMUs

LIST OF ABBREVIATIONS

NE not economic

ND not determined

NA not applicable

s suitable

NS not suitable

LS limited suitability

11-2

11.1 MARBURGS, METAMORPHICS AND GRANITES LAND RESOURCE AREAS

11-3

MARBURGS AND METAMORPHIC$ LAND RESOURCE AREAS

SOIL NUTRIENT STATUS

SURFACE pH

PLANT AVAILABLE WATER CAPACITY

PHYSICAL CHARACTERISTICS

FSI ITCl MF> CSI (TCl !!F AND CSI (TCJ I' M!Us

Low - deficient in minor and major nutrients.

6.0 - 6.5

Very low. 4 em of plant available water stored in the surface A horizon and insignificant

quailtities in the B horizon.

(i) Soil surface sets hard after rain when not protected by vegetation.

{ii) Sob soi1 h<> high bulk density (1.8 - 2.00 g/cc) - root penetration is difficult.

(iii) Sob soil is highly dispersible and hence erodible when exposed.

( iv) Sob soi 1 has high levels of salinity and sodicity.

GRAIN CROPPING FODDER CROPPING SMALL CROPS TREE/VINE CROPS NATIVE PASTURE IMPROVED SOWN

PASTURE

USE SUITABILITY NS

FERTILIZER REQUIREMENTS NA

SUITABLE IMPROVED PASTURE SPECIES NR

PASTURE CARRYING CAPACITY

(ha/b�st)

RUNOFF CONTROL STRUCTURES

(i)

(ii)

(i)

(ii)

NS

NA

Native 5 - 7

Improved NA

Contour banks NS

Waterways NS

Grass species

Fertilizer

NS

NA

NA

NA

(o)

(b)

(c) Construction technique

(iii) Diversion and pondage banks

MAXIMUM PERMISSIBLE VELOCITY (i)

(ii)

(iii)

RUNOFF COEFFICIENT SOIL CATEGORY C

DRAINAGE DESIGN RATING 6.2

SOIL ERODIBILITY (K factor) 0.42 - 0.45

Bare earth channel

Grassed waterway channel

Diversion bank channel

UPPER LAND SLOPE UNIT FOR PERMANENT CULTIVATION NA

UPPER LAND SLOPE LIMIT FOR TREE CLEARING 4%

NA

LAND CAPABILITY CLASSIFICATION VI - VII e6, d6, m4, n4, k4, p4, s2- 4

NA

NA

NS

OTHER INFORMATION Slopes greater than 4% should be used for watershed protection.

NS

NA

Limited summer grazing

NE

Any fonn of management should ensure that water is spread and not concentrated.

Concentration of water will lead to rapid and severe gully erosion of the dispersible sub soil.

NS

NA

11-4

MARBURGS, GRANITES AND METAMORPHIC$ LAND RESOURCE

AREAS

FSI (Ul MF, CSI <Ul MF, CSI <Ul Ge, CSI <Ul M �MUs

SOIL NUTRIENT STATUS Low - deficient in �ajar and minor nutrients

SU RFACE pH - 6. 5

PLANT AVAILABLE WATER CAPACITY Very low - 4 em of plant available water are stored to.

the depth of "parent material.

PHYSICAL CHARACTERISTICS - (il The soil surface sets hard after rain when not protected by vegetation.

USE SU ITAB ll ITY

FERTILIZER REQUIREMENTS

(ii) The sub soil is dispersible.

CRAIN CROPPING FODDER r.ROPPING SMALL CROPS

NS NS NS

TREE/VINE CROPS

NS

NATIVE PASTURE

Limited summer grazing

SUITABLE IMPROVED PASTURE SPECIES - N.R. Creeping blue grass and Siratt'o to be tried in climatic zones B and C.


(ha/beast)

RUNOFF CONTROL STRUCTURES -

MAXIMUM PERMISSIBLE VELOCITY -

(il Native - 5 - 9

(ii) Improved - NA

(il Contour banks - NS

(ii) Waterways - NS

(ol Grass species - NA

(b I Fertilizer - NA



(il Bare earth channel - NA

(ii) Grassed waterway channel - NA

(iii) Diversion bank channel NA

NA

NS

RUNOFF COEFFICIENT SOIL CATEGORY - C

DRAINAGE DESIGN RATING - 6.8

SOIL ERODIBILITY (K factor) 0.25 - 0.31

UPPER LAND SLOPE LIMIT FOR PERMANENT CULTIVATION - NA


LAND CAPABILITY CLASSIFICATION - (i) CSI ( U I M VII - VIII e6, d6, m4, n4, t7-8, r5

OTHER INFORMATION -

(ii) CSI ( U) Gr VI - VII e6, d6, m4, n 4, r4-5, t6-7

(iii) Other units - vr"'- VII e6, d6, m4, n 4

Slopes greater than 4% should be used for watershed protection.

Any form of management should ensure that water is spread and not concentrated.

IMPROVED SOWN PASTURE

NS


SURFACE pH


11-5

MARBURGS LANO RESOURCE AREA

C�\l ( TCJ �IF �MU

Low - deficient in major and minor nutrients.

6.5

Low. Approximately 6 em of plant avai1able water are stored in the surface A horizon

and insignificant quanities in the B horizon.

PHYSICAL CHARACTERISTICS (i) Sub soil has a high bulk density {1.8 - 2.0 g/cc) - root penetration is difficult.

(ii}' Sub soil is highly dispersible and hence erodible when exposed.

(iii) Sub soil has high levels of salinity and sodicity.

GRAIN CROPPING FODDER CROPPING SMALL CROPS TREE/VINE CROPS Nh.TIVE PASTURE IMPROVED SOWN

PASTURE

USE SUITABILITY NS


Temporary prior to establishment of sown pastures.

NP

NS NS s LS

SUITABLE IMPROVED PASTURE SPECIES Rhodes grass, paspalum and medics (where pH> 6.5) in all climatic zones. Creeping blue grass


( ha/beast)


MAXIMUN PERMISSIBLE VELOCITY -

(i)

( i i)

(i)

(ii)

(iii)

(i)

and Siratro in zones B and C.

Native 4.2

Improved 2.6

Contour banks LS

Waterways NS

Grass species

Fertilizer

NA

NA

(o)

(b)


Diversion and pondage banks

Bare earth channel - 0.5 m/sec

(ii) Grassed waterway channel - NA

(iii) Diversion bank channel 0.8 mjsec

RUNOFF COEFFICIENT SOIL CATEGORY - C


SOIL ERODIBILITY (K factor) 0.37

UPPER LAND SLOPE LIMIT FOR PERMANENT CULTIVATION NA


IV - VI e4-6, d4, m4, n4, s2- 4

Banks should be pushed from the outside.

LS

LAND CAPABILITY CLASSIFICATION

OHlER INfORMATION (i) Contour bank outlets should be selected carefully to avoid channel cutback.

(ii) The highly dispersible clay sub soil should not be exposed to running water.

Rapid and severe gully erosion will result.

{iii) Slopes great�r than 7% should be used for watershed protection.


SURFACE pH



11-6

MARBURGS LAND RESOURCE AREA

CD! <TCl MF NIU

Low - deficient in major and minor nutrients.

6.0

Low. The amount stored depends on the depth of the A horizon. Insignificant amounts are

stored in the B horizon.

(i) Sub soil h<tS a high bulk density {1.8- 2.0 g/cc)- root penetration is difficult

(ii) Sub soil is highly dispersible and hence erodible when exposed

(iii) Sub soil has high levels of salinity and sodicity

GRAIN CROPPING FODDER CROPPING SMAL� CROPS TREE/VINE CROPS NATIVE PASTURE IMPROVED SOI-1N

PASTURE

USE SUITABILITY NS


Temporary prior to establishment of sown pastures.

NP

s

NP

NS - except for profi 1 e �'lith A horizon > 60 em

NP

s

NP

SUITABLE IMPROVED PASTURE SPECIES Rhodes grass, paspalum and medics (where pH> 6.0) in all c1imatic zones. White clover in A1

and A2. Kazungula Setaria in B. Creeping blue grass and Siratro in B and C.


{ha/beast)


(i)

{ i i)

(i)

Native 2.0

Improved 3.6

Contour banks NBCB

( i i) Waterways

Grass species

Fertilizer

African star grass, Rhodes grass, Indian blue grass

N, P ,K

(<)

(b)

(o) Construction technique Banks should be pushed from the outside or

topsoil replaced in the channel after

construction (see construction techniques).

(iii) Diversion and pondage banks s

MAXIMUM PERMISSIBLE VELOCITY

RUNOFF COEFFICIENT SOIL CATEGORY


(i)

(ii)

(iii)


Bare earth channel



UPPER LAND SLOPE LIMIT FOR PERMANENT CULTIVATION - 10%

UPPER LAND SLOPE LIMIT FOR TREE CLEARING NO

LAND CAPABILITY CLASSIFICATION III IV e3-4, m3, n3

0 5 mjsec

1.0 m/sec

0.8 m/sec


SURFACE pH

PLANT AVAILAB LE WATER CAPACITY


11-7


CSH (TCJ f1F AND CMH <TCJ MF ,�MUs

Low.

6.5 -7.0

Low to moderate. 9 em of plant available water are stored in the profile to a depth of 60 em.

(i) Sub soil is slowly permeable and erodible if exposed

( ii) The soil surface sets hard after rain when not protected by vegetation

GRAIN CROPPING FODDER CROPPING SMALL CROPS TREE/VINE CROPS NATIVE Pll_STURE IMPROVED SOWN

PASTURE:

USE SUITABILITY


NS

SUITAB LE IMPROVED PASTURE SPECIES


(ha;beast)


MAXIMUM PERMISSIB LE VELOCITY



(i)

(ii)

(i)

(ii)

(iii)

(i)

(ii)

(iii)


s NS NS s s

NP �

Rhodes grass, paspalum and medics (where pH > 6.5) in all climatic zones. Phalaris, fescue

and white clover in Aland A2. White clover in Al, A2 and B. Lucerne in A2, B and C.

Siratro in B and C.

Native 3.6

Improved 2.0

Contour banks NBCB

Waterways s

Grass species

Fertilizer

African star grass, Rhodes grass, Indian blue grass

N,P ,K

(o)

(b)

(c) Construction technique Banks should be pushed from the outside

(see construction techniques)

Diversion and pondage banks s

Bare earth channel 0 5 m/sec

Grassed waterway channel 1.0 m/sec

Diversion bank channel 0.8 m/sec

UPPER LAND SLOPE LIMIT FOR PERMANENT CULTIVATION 8%


LAND Ci\Pi\BlllTY Cli\SSlFlCi\TION IV e3-4, m2. n3, s2


SURFACE pH

Low to moderate.

6.0 - 6.5

118


F�1H <TC) MF .��U



Low to moderate. 8 em of plant available water are stored in the profile to a depth of 60 em.

USE SUITABILITY

FERTILIZER REQUIRE�1ENTS

(i) Soil surface sets hard after rain when not p�otected by vegetation

(ii) The sub soil is dispersible

GF!AIN CROPPING FODDER CROPPING SMA_LL CROPS

NS

N and

TREE/VINE CROPS NATJVE PASTURE

NS s

IMPROVED SOWN

PASTURE

NP

SUITABLE IMPROVED PASTURE SPECIES Rhodes grass, paspalum and medics (where pH > 6.5} in all climatic zones. Phalaris and fescue

in Al and AZ. White clover in Al, A2 and B. Lucerne in A2, B and C. Siratro i� B and C.


(ha/beast)


(i)

(ii)

(i)

(ii)

Native 0

Improved 1. 7

Contour banks NBCB

Waten.�ays s

Grass species

Fertilizer

Kikuyu, Rhodes grass, Indian blue grass

NP

(,)

I b)

(c) Construction technique Banks should be pushed from the outside (see

construction techniques)





(i)

(ii)

(iii)


Bare earth channel




UPPER LAND SLOPE LIMIT FOR TREE CLEARING ND

LAND CAPABILITY CLASSIFICATION IV e3-4, m2, n2, s2, p3

0.5 mjsec

1.0 mjsec

0.8 mjsec

OTHER INFORMATION Contour bank outlets should be selected carefully to avoid channel cutback.

The clay B horizon should not be exposed to running water.

11 9

MARBURGS AND METAMORPHIC$ LAND RESOURCE AREAS

FS-11P ITCl MF, FS-MP <TCl MS, CHIP <TCl MS, CS-MP <TCl I� NIUs

SOIL NUYRIENT STATUS Low to moderate.

SURFACE pH - 6.0 - 7.0

PLANT AVAILABLE WATER CAPACITY Moderate - 10 em of plant available water are stored in the profiie to a depth of 90 em.

PHYSICAL CHARACTERISTICS - (i) Soil surface sets hard after rain when not protected by vegetation.

GRAIN CROPPING FODDER CROPPING SMALL CROPS TREE/VINE CROPS NATIVE PASTURE IMPROVED SOWN

PASTURE

USE SUITABILITY s

NP after FERTILIZER REQUIREMENTS continuous

cultivation

NP after continuous cultivation

NP

LS s

SUITABLE IMPROVED PASTURE SPECIES - Rhodes grass, paspalum and medics (if pH> 6.5) in all climatic zones. Fescue, phalaris and

kikuyu (N required on scrub soi1s) in Al and A2. Lucerne in A2. B and C. Creeping blue

grass and Siratro in B and C. Kazungula Setaria in B. Green panic in all climatic zones

on the scrub soils.


(ha/beast)



(i)

(ii)

(i)

Native - 2.4

Improved - 1.4

Contour banks NBCB

( i i) Waterways -

(o) Grass spec_ies

(b) Fertilizer - NP

Kikuyu, Rhodes grass, Indian blue grass. Substitute African

star grass for kikuyu in CS-MP (TC) MS.

(c) Construction technique - Topsoil should be replaced in the channel.

(iii) Diversion and pondage banks -

(i) Bare earth channel - 0.5 m/sec

(ii) Grassed waterway channel - 1.2 mjsec

(iii) Diversion bank channel 0.8 m/sec

RUNOFF COEFFICIENT SOIL CATEGORY - B


SOIL ERODIBILITY (K factor) - 0.28

UPPER LII.N.D SLOPE LIMn FOR PER�\1\.NENT CULTIVATION - 8%


LAND CAPABILITY CLASSIFICATION - (i) CS-MP (TC) M

(ii) Other units

IV - VI e4-6, m2, n2

III - IV e3-6, m2


SURFACE pH


PHYSICAL CHARACTERISTICS -

11-10

CMI CUl GR Af'1U

Low deficient in major and minor nutrients.

5.5 6.0

GRANITES LAND RESOURCE AREA

LOw. 6 em of plant available water are stored to the depth of the parent material.

(i) Loose friable surface.

GRAIN CROPPnTG FODDER CFIOPPING SMALL CROPS THEE/VINE CROPS NATIF/E PASTURE

USE SUITABILITY NS


temporary prior to establishment of sown pastures

NP

NS NS s

IMPROVED SOWN

PASTURE

LS

SUITABLE IMPROVED PASTURE SPECIES Rhodes grass, paspalum and medics (where pH> 6.5) in a11 climatic zones. White c1over in

zones Al and A2. Creeping blue grass and Siratro in zone B.


(ha/beast)



(i)

( i i)

(i)

(ii)

{iii)

Native 4.2

Improved 2.6

Contour banks LS

Waterways NS

Grass species

Fertiljzer

NA

NA

(a)

I bl



Bare earth channel 0.5 mjsec

Grassed waterway channel NA

Banks should be pushed from the outside.

LS

(i)

(ii)

{iii) Diversion bank channel 0.8 m/sec

RUNOFF COEFFICIENT SOIL CATEGORY B



UPPER LAND SLOPE Lit�IT FOR PERMANENT CULTIVATION NA


LAND CAPABILITY CLASSIFICATION IV - VI e4-6, m4, n3, t6, d4.

11-11

GRANITES LAND RESOURCE AREA

CS-MP (TCJ Ge AMU

SOIL NUTRIENT STATUS Low to moderate - deficient in N and P and possibly K.

SURFACE pH 6.5 -7.0

PLANT AVAILABLE WATE.=< CAPACITY Moderate. 10 em of plant available water are stored in the profile to a depth of 90 em.


USE SUITABILITY


(i) The soil socf,ce sets hacd 'ftec caio wheo·oot pcotected by 'eget,tioo,

GRAIN CROPPING

s

NP

FODDER CROPPING

s

NP

SMALL CROPS

s

NP

TREE/VINE CROPS

S - LS

NATIVE PASTURE

s

IMPROVED SOWN PASTUHE

s

NP

SUITABLE IMPROVED PASTURE SPECIES Rhodes grass, paspalum, medics (if pH > 6 5) and white clover in climatic zones Al, A2 and B.

Fescue and phal_aris in Al and A2. Lucerne in AZ and B. Creeping blue grass, Kazungula

Setaria and Siratro in B.


( ha/beast)


(i)

(ii)

(i)

(ii)

Native 2.4

Improved 1.6

Contour banks NBCB

Waterways s

Grass species

Fertilizer


N,P,K

(a)

(b)

(c) Construction technique Topsoil should be replaced in the channel.



(ii)

(iii)




Bare earth channel

Grassed wt�terway channel


UPPER LAND SLOPE LIMIT FOR PERMANENT CULTIVATION 8 %


LAND CAPABILITY CLASSIFICATION III - IV e3-4, m3, n2

0.5 m/sec

1.0 mjsec

··o.s m/sec

11-12

GRANITES LA.T'ID RESOURCE AREA


SURFACE pH -

COP <TCl GR AMU

Low to moderate - deficient in �J and P and possibly K

6.5 - 7.0

Pl�.NT AVA1LABLE WATER Ci'IP!l.CITY \-loderate - 8 to 10 em of p1 ant available water are stored in the profile to a depth of 90 em.

PHYSICAL CHARACTERISTICS - (i)

GRAIN CROPPING

USE SUITABILITY


LS

NP

The soil surface sets hard after rain when not protected by vegetation.

FODDER CROPPING

NP

SMALL CROPS

s

NP

TREF:/VINE CROPS NATIVE PASTURE

s

NP


s

NP

SUITABLE IMPROVED PASTURE SPECIES Rhodes grass, paspalum, medics (where pH> 6.5) and white clover for climatic zones Al, A2

and B. Phalaris and fescue in Al and A2. Lucerne in A2 and B. Creeping blue grass,

Kazungula Setaria and Siratro in B.

PATURE CARRYING CAPACITY

(hajbeast)

(i)

(; i)

Native - 2.4

Improved � 1 6


t'l.AXIMUM PERMISSIBLE VELOCITY -

(i) Contour banks - NBCB

(ii) Waterways - S

(a) Grass sp�cies - Kikuyu, Rhodes grass, Indian blue grass

(b) Ferti1 izer - N,P,K


(iii) Diversion and pondage banks - S

(i) Bare earth channel - 0.5 m/sec

Topsoil should be replaced in the channel.

(ii) Grassed waterway channel - 1.0 m;sec

(iii) Diversion bank channel 0.8 m/sec

RUNOFF COEFFICIENT SOIL CATEGORY - A


SOIL ERODIBILITY {K factor) 0.18

UPPER LAND SLOPE LIMIT FOR PERMANENT CULTIVATION - 10%

UPPER LAND SLOPE LIMIT FOR TREE CLEARING - NO

LAND CAPABILITY C LASSIFICATION - III - IV e3-4, m3, n2


SURFACE pH

Moderate to high.

6.0- 7.0

METAMORPHICS LAND RESOURCE AREA

FS-MP IGl M AMU



Moderate. 11 em of plant available water are stor.ed in the profile to a depth of 90 em.

USE SUITABILITY

(i) The soil surface sets hard after rain when not protected by vegetation.

GRIIIN CROPPING FODDER CROPPING SMALL CROPS TREE/VINE CROPS NATIVE PAS'IVHE

s s s

N and P after FERTILIZER REQUIREMENTS continuous

N and P after continuous cultivation

NP NP cultivation

IMPROVED SOJ.IN

PASTURE

s

SUITABLE IMPROVED PASTURE SPECIES Rhodes grass, paspalum, medics (where pH> 6.5) and white clover in climatic zones Al, A2

and B. Fescue, phalaris and kikuyu (if N is applied) in Aland A2. Lucerne in A2 and B.

Creeping blue grass, Kazungula Setaria and Siratro in B.


( ha/beast)


(i)

(ii)

(i)

( i i)

Native 2.4

Improved 1.4

Contour banks NBCB

Waterways s

Grass species

Fertilizer


N,P

(e)

(b)

(c) Construction technique Standard



(ii)

(iii)

Bare earth channel 0.6 m/sec

RUNOFF COEFFICIENT SOIL CATEGORY A


SOIL ERODIBlllT'1 (K factor) 0.25




UPPER LAND SLOPE LIMIT FOR TREE CLEARING ND

LAND CAPABILITY CLASSIFICATION III VI e3-6, m2, n2

1.2 m/sec

. 0 m/sec

11-14

11.2 BASALT WEST LAND RESOURCE AREA

SOIL NUTRIENT STATUS High

SURFACE pH 6.5 7.0


PHYSICAL CHARACTERISTICS (i)

11-15

BASALT WEST LAND RESOURCE AREA

Mapping Symbol - Ke

Very 1 ow

S-hallow soil depth

(ii) Large amounts of stone and rock on the SLirface and throughout the profile.

USE SUITABILITY


GFAIN CROPPING

NS

FODDER CROPPING SMALL CROPS

NS

TREE/VINE CROPS NATIVE PASTURE

NS NS

IMPROVED SOW/Jl PASTURE

s

p .s

SUITABLE IMPROVED PASTURE SPECIES Green panic, Rhodes grass, creeping blue grass, medics and lucerne (This AMU only occurs in clil'laticzone C)


(ha/beast}


{i)

{ii)

{i)

(ii)

Native 2.4

Improved

Contour banks

Waterways NS

(a) Grass species

(b) Fertilizer

NS


(iii) Diversion and Pondage banks



DRAINAGE DESIGN RATING NA

(i)

(ii}

(iii)


Bare earth channel

Grassed waterway chaline 1


UPPER LAND SLOPE LIMIT FOR PERMANENT CULTIVATION NS

UPPER LAND SLOPE LIMIT FOR TREE CLEARING - 17 - 20% (interim)

VI e4-6, m3, d4-6, r3-5

NA

N A


OTHER INFORMATION (i) In certain locations, grassed areas of this unit provide valuable water dispersal areas for

contour banks from adjoining cultivation and eliminate the need for waterways.

(ii) Because of steepness and stoniness.pasture seed cannot be drilled and must be broadcast.

11-16

BASALT WEST LAND RESOURCE AREA

PURRA!jUNDA AMU

Mapping Symbol - Pu . c

SOIL NUTRIENT STATUS High

SURFACE pH 7.5

PLANT AVAILABLE WATER CAPACITY Moderate but depends on soil depth to decomposing basalt. A profile with a decomposing basalt

layer at 6Q em will hohi between 9 and 12 em of plant available water to that depth .


USE SUITABILITY


(i) StrOng medium granular structure

{ii) Cracking

GRAIN CROPPING

s

N and P after continuous cultivation

FODDER CROPPING

and P after continuous cultivation

SMALL CROPS

LS

TREE/HNE CROPS NATIVE PASTURE

NS s

IMPROVED SOWN

PP.STURE

s

P,S

SUITABLE IMPROVED PASTURE SPECIES Green panic, Makarikari grass (cv. Bambatsi), Rhodes grass, lucerne and medics (This AMU only


{hajbeast)


(i)

( i i)

(i)

(ii)

(iii)

MAXIMUM PERMISSIBLE VELOCITY - (i)

(ii)

(iii)




occurs in climatic zone C).

Native 2.4

Improved NA

Contour banks BBTS

Waterways s

(e)

(b)

(o)

Grass species Kikuyu, African star grass, Indian blue grass

Fertilizer N

Construction technique



Standard

s

Grassed waterway channel 1.2 mjsec



UPPER LAND SLOPE LIMIT FOR TREE CLEARING 17-20% (interim)


01HER 1NFORMA11DN

II - IV e2-4

(i) lhe deep phase of this soll (> 75 mm) may occur in association with the Irving clay and is

regarded as having the same limitations and management requirements as the Irving AMU.

(ii) Stubble mulching and/or minimum tillage are recommended to reduce soil erosion.

11-17

11.3 BASALT EAST LAND RESOURCE AREA

11-18

BASALT EAST LAND RESOURCE AREA

BFs AND BSs AI'U'

Mapping Symbol - BFs and BSs

SOIL NUTRIENT STATUS High. Nitrogen is high. Phosphorus is high to very high. ,Potassium is marginal to adequate.

SURFACE pH 6. 5 7.0

PLANT AVAILABLE WATER CAPACITY - Very low

PHYSICAL C\-lA.RACTERlSTlCS

USE SUITABILITY


li) Shallow soil depth

(ii) Large amounts of stone and rock throughout the profile

GBAIN CROPPING FODDER CROPPING SMALL CROPS TREE/VINE CROPS

NS NS NS NS

NATIVE PASTURE

s

II1PROv:ED SOWN PASTURE

s

N ,P ,S

SUITABLE IMPROVED PASTURE SPECIES Rhodes grass, green panic, paspalum, Kazungula Setaria, creeping blue grass, white clover,


(ha/beast)

lil

( i i)

RUNOFF CONTROL STRUCTURES (i)

( ii)

Siratro and medics (This AMU only occurs in climatic zone B).

Native 2.0 - 2.4

Improved 1.2 - 1.6

Contour banks NS

Waterways NS

lo) Grass species

I b) Fertilizer

lei Construction technique



( i i)

(iii)

RUNOFF COEFFICIENT SOIL CATEGORY 8

DRAINAGE DESIGN RA1ltffi NA


Bare earth channel NA


Diversion bank channel NA


UPPER LAND SLOPE LIMIT FOR TREE CLEARING 17 20% (interim)


OTHER INFORMATION

VI - VII e6, m3, d4-6, r4-S, t6-7

Iii Because of steepness and stoniness,seed cannot be drilled and must be broadcast.

11-19


BSn A14U

Mapping Symbol - BSd

SOIL NUTRIENT STATUS High. Nitrogen is initially high. Phosphorus is very high. Potassium is adequate. This soil often occurs

SURFACE pH 6.5

in complexes with sandstone derived soils of low nutrient status.

PLANT AVAILABLE WATER CAPACITY Moderate to high but depends on soil depth. The plant available water capacity for a profile

to a depth of 90 em would vary from 14 to 19 em.


USE SUITABILITY


(i) Well structured surface

(ii) Cracking soil

GRAIN CROPPING

s

NP

FODDER CROPPING

s

NP

SMALL CROPS TREE/VINE CROPS

LS NS

NATIVE PASTURE

s


N,P,S

SUITABLE IMPROVED PASTURE SPECIES Rhodes grass, green panlC, paspalum, Kazungula Setaria, creeping blue grass, white clover,

Siratro, medics and lucerne (This AMU only occurs in climatic zone B).


(ha/beast)


(i)

(ii)

(i)

(ii)

(iii)


(ii)

(; i i)




Native 2.0 - 2.4

Improved 1.2 1.6

Contour banks NBCB (some soil cracking does occur)

Waterways

1•1

(b)

(o)

Grass species Kikuyu, African star 9rass, Rhodes grass, Indian blue grass

Fertil-izer N




Standard

s



UPPER LAND SLOPE LIMIT FOR PE�MP_NP!T CULTIVATION - 8%


LAND CAPABILITY CLASSIFICATION III VI e3-6

OTHER INFORMATION (i) Stubble mulching and/or minimum tillage are recommended to reduce soil erosion.


BFn AMU

�lapping Symbol - BFd

SOIL NUTRIENT STATUS High. Nitrogen is fair. Phosphorus is high. Potassillm is adequate.

SURFACE pH 6.5 7.0

PLANT AVAILABLE WATER CAPACITY Moderate to high but depends on soil depth. The plant available water capacity for a profile

to a depth of 90 em would vary from 14 to 19 em. Moisture stress will occur in the shallow phase.


USE SUITABILITY


(i) Strongly structured surface

(ii) Crac.�ing

GRAIN CROPPING FODDER CROPPING

s s

NP N P

SMALL CROPS

LS

TREE/VINE CROPS NATIVE PASTURE

NS s

IMPROVED SOf!N PASTURE

s

N ,P ,S

SUITABLE IMPROVED PASTURE SPECIES Rhodes grass, green panic, paspalum, Kazungula Setaria, creeping blue grass, while clover,


(ha/beast)


(i)

( i i)

(i)

('ii)

(iii)

MAXIMUM PERMISSIBLE VELOCITY - ( i)

(ii)

(iii)

RUNOFF COEFFICIE<H SOIL CATEGORY



Siratro, medics and lucerne (This AMU only occurs in climatic zone B).

Native

Improved

2.0 - 2.4

1.2 - 1.6

Contour banks - NBCB (some soil cracking does occur)

Waterways 5

(,)

I b)

(c)

Grass species Kikuyu, African star grass, Rhodes grass, Indian blue grass

Ferti 1 i zer N


Diversion and pondage banks 5

Bare earth channel 0.5 m;sec

Standard






OTHER INFORMATION

III - VI e3-6

(i) Stubble mulching and minimum tillage are recommended to reduce inter bank erosion.

11-21


BFwn AMU

Mapping Symbol - BFwd


SURFACE pH 6.5

Moderately high. Nitrogen is fair to high. Phosphorus is very high. Potassium is adequate.

PLANT AVAILABLE WATER CAPACITY Moderate to high but depends on soil depth. The plant available water capacity for a profile to a

dept\'1 of 90 em would vary from 14 to 19 Clll.

PHYSICAL CHARACTERISTICS (i) Surface structure deteriorates with Continuous cultivation.

GRAIN CROPPING FODDER CROPPING SMALL CROPS TREE/VINE CROPS NATIV!l' PASTURE IMPROVED SOWN

PASTURE

USE SUITABILITY


SUITABLE IMPROVED PASTURE SPECIES


{ha/beast)


s

NPS

(i)

(ii)

(i)

(ii)

s LS NS

NPS

Rhodes grass, paspalum, creeping blue grass, Kazungula Setaria, white clover, lucerne,

Siratro and medics.

Native 2.0 2.4

Improved 1.2 - 1.6

Contour banks NBCB

Waterways s

s

NPS

(e)

(b)

(c)

Grass species Kikuyu, African star grass, Rhodes grass, Indian blue grass

{iii)

MAXIMUM PERMISSIBLE VELOCITY - {i)

{ i i)

(iii)

RlJNOFF CQE.FFlClENi SOil CATEGORY B



Fertilizer N



Bare earth channel 0 5 m/sec

Standard


Diversion bank channel 0 mjsec

UPPER LAND SLOPE LIMIT FOR PERt·1ANENT CULTIVATION - 8%

UPPER LAND SLOPE LIMIT FOR TREE CLEARING 17 - 20% (interim)

LAND CAPABILITY CLASSIFICATION III VI e3-6, m2, p2, dl-2

01HER INFORMATION (i) A crop rotation system which includes a pasture ley is recommended to maintain surface

soi 1 structure.

{ii) Stubble mulching and/or minimum tillage are recoTmJended to reduce interbank erosion.

11-22

11.4 BASALTIC RED SOILS LAND RESOURCE AREA

BASAL TIC RED SOILS LAND RESOURCE AREA

CABARLAH AMU

Mapping Symbol Cab


SURFACE pH 5.8

Very low.

PLANT AVAILABLE WATER CAPACITY Low.


USE SUITABILITY


(i) Shallow soil depth

(ii) Stone and gravel on the surface and throughout the profile

(iii) Soil surface is moderately weak to structureless

( iv} Well drained soil


NS NS


NS NS

NATIVE PASTURE

s


s

N, P ,S Mo every 5 years

SUITABLE IMPROVED PASTURE SPECIES Rhodes grass and paspalum in all climatic zones. White clover in zones Al, A2 and B. Kikuyu,

phalaris and fescue in zones Al and A2. Kazungula Setaria in zone B. Siratro and creeping

blue grass in zones B and C.

PASTURE CARRYING CAPACITY (ha/beast}


(i)

( ii}

(i)

(ii)

(iii)

Native 1.1 2.4

Improved 0.7 - 1.2

Contour banks NS

Modified contour banks/beds

Waterways NS

Grass species

Fertilizer NA

NA (,)

(b)


( iv)


(ii)


DRAINAGE DESIGN RATING NA



Bare earth channel NA


UPPER LAND SLOPE LIMIT FOR PERMANENT CULTIVATION NS

UPPER LAND SLOPE LIMIT FOR TREE CLEARING 17- 20% (interim)

LAND CAPABILITY CLASSIFICATION V - VI e3-6, m4, n3, d4-6, r3-5

NS

NA

s

OTHER INFORMATION (i) Because of stoniness, pasture seed cannot be drilled and must be broadcast.

11-24


PECHEY A'1U

Mapping Symbol Pey

SOIL NUTRIENT STATUS Low. Nitrogen is initially moderate but decreases rapidly with cultivation. Phosphorus is low.

SURFACE pH 6.2



Potassium is low to fair.

Modero.te to high.

(i)

{ii)

{iii) -

Well drained soil

Soil surface is structureless (snuffy)

Rainfall is initially absorbed very slowly

GRAIN CROPPING FODDER CROPPING SMALL CROPS TREE/VINE CROPS

USE SUITABILITY


LS

NPK

s

NPK

NATIVE PASTURE

s

Il1PROVED SOWN

PASTURE

s

NPS Mo every 5 years.

SUITABLE IMPROVED PASTURE SPECIES


( ha/beast)


(i)

{ii)

(i)

( i i)

(iii)

(iv)


(ii)

(iii)



SOIL ERODIBILITY (K factor) 0.26-

Rhodes grass and paspalum in all climatic zones. White clover in zones Al, A2 and B.

Kikuyu, phalaris and fescue in zones A1 and A2. Lucerne in zonesA2. B and c. Kazungula

Setaria in zone B. Siratro and creepin') blue grass in zones B and C.

Native 1.1 - 2.4

Improved 0. 7 - 1. 2

Contour banks NBCB


Waterways s -

s

(<)

(b)

(c)

Grass species Kikuyu, Rhodes grass, Indian blue grass

Fertilizer N,P ,K

Construction technique Either constructed from the outside or topsoil replaced



after excavation.


Diversion bank channel 0.8 mjsec

UPPER LAND SLOPE LIMIT FOR PEP�'.IlNENT CULTH�TON 8%


LAND CAPABILITY CLASSIFICATION III IV e2-4, m2, n2, p2

OTHER INFORMATION (i) The use of nitrogenous fertilizer on dairy pastures in climatic zone A can be an

economic practice.

{ii) Rolling is recommended for pasture establishment.

11-25

PALmREE AMU

Mapping Symbol - Pal

SOIL NUTRIENT STATUS Nitrogen is initially high but decreases rapidly with cultivation. Potassium is generally adequate.

SURFACE pH 5.8

Phosphorus is variable and varies from fair to high.


PHYSICAL CHARACTE Rl S TICS (i)

Moderate to high

Internal drainage is slow below 60 em

USE SUITABILITY


{ii) Moderate surface structure

GRAIN CROPPING FODDER CROPPING SMALL CROPS

LS (suitable for 1 imited winter)

NP

s

NP

THEE/VINE CROPS NATIVE PASTURE

s

fl1PROVED SOWN PASTURE

s

N,P,S Mo every 5 years

SUITABLE IMPROVED PASTURE SPECIES Rhodes grass, pas palum and green panic in all climatic zones. ��hite clover in zones Al, A2 and

PASTURE CARRYING CAPACITY {ha./beast)


(i)

( i i)

(i)

( i i)

(iii)

B. Kikuyu, phalaris and fescue in zones Al and A2. Lucerne in zones A2, 8 and C. Kazungula

Setaria in zone B. Siratro and creeping blue grass in .zones Band C'.

Native

Improved

Contour banks

1 - 2.4

0.7 - 1.2

NBCB


Waterways s

s

1,1

(b)

(c)

Grass s pecies Kikuyu, Rhodes grass, Indian blue grass

Fertilizer N, P ,K


after excavation.

( iv) Diversion and pondage banks


( j i)

(iii)





Grassed waterway channe1 1.2 m/sec



UPPER LAND SLDPE LIMIT FOR TREE CLEARING 17 20% (interim)

LAND CAPABILITY CLASSIFICATION III VI e3-6, m2, nl-2

OTHER INFORMATION {i) The use of nitrogenous fertilizer on dairy pastures in climatic zone A can be an economic

practice.

11-26

BASALTIC RED SOILS LAND RESOURCE AREA

GEHAfl .�MU

Mapping Symbol Geh

SOIL NUTRIENT STATUS Low. Nitrogen is initially fair but declines rapidly with cultivation. Potassium is low to adequate.

SURFII.CE pH 6.2



Phosphorus is very low.

Moderate.

(i) Subsoil is slowly penneable

(ii) Perched watertable may be present

GRAIN CROPPING FODDER CROPPING S/1ALL CROPS

USE SUITABILITY LS s LS

FERTILIZER REQUIREMENTS NPK NPK

TREE/VINE CROPS

NS (due to impeded drainage)

NATIVE PASTURE

s


NPS Mo every 5 years.

SUITABLE IMPROVED PASTURE SPECIES Rhodes grass and paspalum in all climatic zones. \�hite clover in zones Al, A2 and B. Kikuyu,

phalaris and fescue in zones Al and A2. Lucerne in zones A2, B and C. Kazungula Setaria

in zone B. Siratro and creeping blue grass in zones B and C.

PASTURE CARRYING CAPACITY ( ha/beast)


(i)

(ii)

(i)

Native

Improved

Contour banks

1.1 2.4

0.7 - 1.2

NBCB

( i;) Modified contour banks/beds

{iii) waterways

Grass species Kikuyu, Rhodes grass, Indian blue grass (a)

(b)

(ol

Fertilizer N, P ,K


after excavation.

(iv) Diversion and pondage banks s


{ii)

(iii)

RUNOFF COEFF1CIENI SOil CA1EGORY B



Bare earth channel




UPPER lAND SLOPE LIMIT FOR TREE CLEARING 17 - 20% (interim)

LAND CAPABILIIY CLASSIFICATION III IV e2-4, m2, n2, p2

0. 5 m/sec

1.2 mjsec

0 .8 m/sec

OIHER INFORMATION ( ;) Roll in� is recommended for pasture establishment

(ii) The use of nitrogenous fertilizer on dairy pastures in climatic zone A can be an

economic practice.

11-27


RAVENSBOURNE P.MU

Mapping Sjffllbol Rav


SURFACE pH 5.5

�loderate. Nitr ogen is initially very high. Phosphorus is generally low but variable. Potassium is adequate.



11odera te to high.

(i) Very well drained, deep soil

( i i) Moderate surface structure

GRAIN CROPPING FODDER CROPPING SMALL CROPS

USE SUITABILITY

FERTILIZER REQUIREI�ENTS

s

NP

s s

NP

TREE/VINE CROPS NATXVE PASTURE

s s

IMPROVED S0\>1/1

PASTURE

s

NP Mo every 5 years

SUITABLE IMPROVED PASTURE SPECIES Rhodes grass. paspalum and green panic in all climatic zones. White clover in zonesAl, A2 and B.


{hajbeast)

RUNOFf CONTROL STRUCTURES

(i)

( i i)

\i)

Kikuyu, phalaris and fescue in zones Al and A2. Lucerne in zones A2, B and C. Kazungula

Setaria in zone B. Siratro and creeping blue grass in zones B and C.

Native

Improved 0.7 - 1.1

Contour banks NBCB

(ii) Modified contour banks/beds

(iii)

(iv)


( ii)

(iii)



SOIL ERODIBILITY {K factor) 0.24

Waterways s

(<)

(b)

(o)


Fertilizer N, P ,K




after excavation.

s

Grassed water;vay channel 1.2 m/sec

Diversion bank channel 0.8m/sec



LAND CAPABILITY CLASSIFICATION IV - VI e4-6, mZ, nl-2

OTHER INFORMATION The use of nitrogenous fertilizer on dairy pastures in climatic zone A can be an economic practice.

SOIL NUTRIENT STATUS (i)

11-28


PINELANDS 1 AND 2 AMU s

Mapping Symbol - Pin

Pinelands 1 - Nitrogen is initially high. Phosphorus is very high. Potassim is adequate

to high.

{ii) Pinelands 2 - Nitrogen is fair. Phosphorus is very high. Potassium is deficient to

SURFACE pH (i)

(ii)

marginal.

Pinel ands 7.2

Pine lands 5.0

PLANT AVAILABLE WATER CAPACITY High


USE SUITABILITY


(i) Pinelands 1 (a) Well structured surface

(b) Stone occurs throughout the profile

(ii) Pinelands 2 - {a) Surface is structureless

GRAIN CROPPING

LS

NP

FODDER CROPPING

s

NP

SM/,LL CROPS TREF;/VINE CROPS

s

NATIVE PASTURE

s

IMI?FIOVED SOWN PASTURE

s

NP

SUITABLE IMPROVED PASTURE SPECIES Rhodes grass, paspalum, green panic and creeping blue grass in all zones. White clover in

PASTURE CARRYING CAPACITY (i)

( ha/beast) ( i i)

RUNOFF CONTROL STRUCTURES (i)

(ii)

(iii)

(iv)


(ii)

(iii)

RUNOFF COEFFICIENT SOIL CATEGORY f;



zones Al, AZ and B. Kikuyu, phalaris and fescue in zones Aland AZ. Lucerne in zones AZ,

B, C. Kazungula Setaria in zone B. Siratro in zones B and C.

Native

Improved 0. 7 - 1.1

Contour banks - rJBGB

Modified contour banks/beds s

Waterways

(o)

(b)

I c)

Grass species Kikuyu, Rhodes \)rass, Indian blue grass

Ferti1izer N,P,K




Either constructed from the outside or topsoil replaced

after excavation.

s


Grassed diversion bank channel 0.8 m/sec

UPPER LAND SLOPE LIMIT FOR PERtlANENT CULTIVATION - 10%


LAND CAPABILITY CLASSIFICATION IV - VI e4-6, m2, nl-2

11-29


�1ERRITTS Ai'1U

Mapping Symbol � Mer

SOIL NUTRIENT STATUS Nitrogen is initially high. Phosphorus is fair to high. Potassium is generally adequate. Responses to

molybdenum and sulphur have been reported.

SURFACE pH 5.8



Moderate

(i) Well structured surface

( i i} Cracking

GRAIN CROP?ING FODDER CROPPING

USE SUITABILITY

FERTILIZER REQUIREI�ENTS

s

NP NP


LS NS

NATIVE PASTURE IMPROVED SOWN

PASTURE

N,P,S Mo every 5 years

SUITABLE IMPROVED PASTURE SPECIES Rhodes grass, p""spalum and medics in all climatic zones. White clover is zones Al, A2 and B.


( hajbeast)


(i)

( il)

(i)

(ii)

(;; i)

(iv)


( i i)

(iii)




Kikuyu, phahris and fescue in zones Al and A2. Lucerne in zones A2, B and C. Kazungula

Setaria in zone B. Siratro and creeping blue grass in zones B and C.

Native

lmproved

1.1 -

0. 7

4

l.2

Contour banks NBCB (even though some soil cracking occurs)

Modified contour banks/beds s

Waterways s

(e)

(b)


Fertilizer N, P ,K




s

Grassed waterway channel 1.2 mjsec


UPPER LAND SLOPE LIMIT FOR PERMANENT CUL TlVATION 8%

UPPER LI\ND SLOPE LIMIT FOR TREE CLEARING 17 - 20% {interim)

LAND CAPABILITY CLASSIFlCATION III VI e3-6, nl-2

OTHER IN�'"ORMATION {i) The use of nitrogenous fertilizer on dairy pastures in climatic zone A can be an

economic practice.

11-30

11.5 ALLUVIUM LAND RESOURCE AREA

11-.)1

ALLUVIUM LAND RESOURCE AREA


SURFACE pH -

Very high

7.5

WACO AI'U

PLANT AVAILABLE WATER CAPACITY High. The plant available water capacity of a pro,file to a depth of 90 em would

approximate 20 em.

PHYSICAL CHARACTERISTICS - (i) Self mulching

(ii) Cracking

GRAIN CROPPING

USE SUITABILITY 5

N and P FERTILIZER REQUIREMENTS after continuous

cultivation

FODDER CROPPING

N and P after continuous

cultivation

SMALL CROPS TREE/VINE CROPS NATIVE PASTURE

LS NS s

SUITABLE IMPROVED PASTURE SPECIES - Rhodes grass, green panic, creeping blue grass, Makarikari grass (cv. Bambatsi),

PASTURE CARRYING CAPACITY -

RUNOFF CONTROL STRUCTURE-S -


(i)

(ii)

(i )

(ii)

(iii)

(i)

( ii)

(iii)

RUNOFF COEFFICIENT SOIL CATEGORY - B

DRAINAGE DESIGN RATING -

SOIL ERODIBILITY (K factor )

Columbus grass, lucerne, Jemalong barrel and snail medics.

Native NA

Improved NA

Contour banks s

Waterways s

Grass species Kikuyu, African star grass, Indian blue grass

Fertilizer NP

(o)

(b)

(c) Construction technique standard





UPPER LAND SLOPE LIMIT FOR PERMANENT CULTIVATION - NA

UPPER l!I.NO SLOPE LIMIT fOR 1REE CLEJ\RlNG - Nil.

LAND CAPABILITY CLASSIFICA110N - I - II e l-2


s


SURFACE pH -

Moderate

6.0- 7.0

11-32


ALS AMU

PLANT AVAILABLE WATER CAPACITY Moderate to high - approximately 15 em of plant available water are stored in the

profi 1 e to a depth of 90 em.

PHYSICAL CHARACTERISTICS - Iii' Strong fine surface structure

USE SUITABILITY

( i i) Cracking


s

N and N and FERTILIZER REQUIREMENTS after continuous after continuous

cultivation cultivation

SMALL CROPS

LS

TREE/V DIE CROPS NATIVE PASTURE

HS s

IMPROVED SOWN PASTU'RE

s

p

SUITABLE IMPROVED PASTURE SPECIES - Rhodes grass, green panic, paspalum, creeping blue grass, kikuyu (in favourable areas),

white clover, lucerne and medics.



(i)

(ii)

(i)

( i i)

Native

Improved NA

Contour banks s

Waterways s

Grass species African star grass, kikuyu, Indian blue grass

Fertilizer NP

(o)

(b)




(ii)

(iii)


DRAINAGE DESIGN RATING

SOIL ERODIBILITY (K factor)

Bare earth channel




UPPER LAND SLOPE LIMil FOR TREE CLEARING NA

LAND CAPABILITY CLASSIFICATION I - II el-2

0.5 m/sec

1.2 m/sec

0.8 m/sec


SURFACE pH -


PHYSICAL CHARACTERISTICS -

11-33


ALW AMU

Moderate

6. 5

Moderate. Approximately 11 em of plant available water are stored in the profile

to a depth of 90 em.

(i) Weak surface structure

(ii) Surface crusting

GRAIN CROPPING FODDER CROPPING SMALL CROPS TREE/VINE CROPS NATIVE PASTURE

USE SUITABILITY


5

NP NP

LS NS s

IMPROVED SOWN

PASTURE

s

SUITABLE IMPROVED PASTURE SPECIES Rhodes grass, green panic, paspalum, creeping blue grass, kikuyu (in favourable areas), white



clover and lucerne.

(i) Native - NA

( i i) Improved - NA

(i)

( i i)

Contour banks

Waterways

s

s

Grass species

Fertilizer

African star grass, kikuyu, Rhodes grass, Indian blue grass

NPK

(')

(b)

(o) Construction technique standard






(i)

(ii)

(iii)

Bare earth channel




UPPER LAND SLOPE LIMIT FOR TREE CLEARING NA

LAND CAPABILITY CLASSIFICATION II ei-2, p2

0.5 m/sec

1.2 m/sec

0.8 mjsec

11-34



SURFACE pH

Low to moderate.

5.5 to 6.0

ALH ��u

PLANT AVAILABLE WATER CAPACITY Low to moderate - approximately 8 em of plant available water are stored in the profile

to a depth of 60 ern.

PHYSICAL CHARACTERISTICS The soil surface sets hard.

GRAIN CROPPING FODDER CROPPING SMALL CROPS TREE/VINE CROPS

USE SUITABILITY s s LS NS

FERTILIZER REQUIREMENTS NP NP

SUITABLE IMPROVED PASTURE SPECIES Rhodes grass, creeping blue grass, paspalum, medics, lucerne,

PASTURE CARRYING CAPACITY (i) Native 2.4

(ha/beast) (ii) Improved 1.4

RUNOFF CONTROL STRUCTURES (i) Contour banks

(ii) Waterways

s

NATIVE PASTURE

s

white clover,

IMPROVED SOWN

PASTURE

p

Siratro.

(o) Grass species African star grass, kikuyu (with extra N), Rhodes grass,

Indian blue grass

Fertilizer N,P,K (b)




(ii)

(iii)




Bare earth channel




UPPER LAND SLOPE LIMIT FOR TREE CLEARING NA

LAND CAPABILITY CLASSIFICATION rrr el-2, m2, n2, p2

0 5 m/sec

1.2 m/sec

0.8 m/sec

12-1

BIBLIOGRAPHY

Anon. - Soil Conservation Handbook, Queensland. Soil Conservation Branch, Qd Dep. Prim. Inds.

Bierenbroodspot, J. (1967) - Water spreading on pastures. Qd Agrie. J. 93:259-61.

Bierenbroodspot, J. (1972) -Contour banks and erosion. Qd Agrie. J. 98:259-60.

Cranfield, L.C. , Schwarzbock, H. and Day, R.W. (1976) - The geology of the Ipswich and Brisbane 1:250 000 sheet areas. Geological Survey of Queensland No. 95.

Cull, J. (1972) - "Crow' s Nest Shire Handbook". Qd Dep. Prim. Inds., Brisbane.

Holmes, K.H. (1981) - Land stability on the eastern slopes of Toowoomba. Geological Survey of Queensland. Record Series.

Lehmann, G.M. and Bartels, H. with a farm dozer. Prim. Inds.

(1978a) - Build your contour banks Soil Conservation Branch, Qd Dep.

Lehmann, G.M. and Bartels, H. (1978b) - Build your waterways with a farm dozer. Soil Conservation Branch, Qd Dep. Prim. Inds.

Marshall, J., Mullins, J., Freebairn, D., Donnollan, T., Glanville, S. and Crothers, R. (1980) - Erosion survey for the Clifton, Cambooya and Pittsworth Shires eastern Darling Downs after the storm events of the 26.1.80 to 5.2.80. Teeh. Report Div. Ld Util. Qd Dep. Prim. Inds. No. 80/15.

Mullins, J.A. (1977) - The dispersion test. Teehnieal Nevs SoiZ Conservation Darling Dovns Region 1:14-15.

Mullins, J.A. (1978) - Description and management the eastern Darling Downs, Queensland. Ld UtiZ. Qd Dep. Prim. Inds. No. 33.

of the soils of Teeh. BuZZ . Div.

Murphy, P.R., Schwarzbock, H., Cranfield, L.C., Withnall, I.W. and Murray, C.G. (1976) - Geology of the Gympie 1:250 000 sheet area. Geological Survey of Queensland No. 96.

Nevell, P.P., Truong, P.N. and Turner, E.J. (1981) - Conservation grazing management. Teeh. Report Div. Ld UtiZ. Qd Dep. Prim. Inds. No. 81/1.

12-2

Rosenthal, K.M. and White, B.J. (1980) - Distribution of a rainfall erosion index in Queensland. Tech. Report Div. Ld Util. Qd Dep. Prim. Inds. No. 80/8.

Rosser, J., Swartz, G.L., Dawson, N.M. and Briggs, H.S. (1974) -A land capability classification for agricultural purposes. Tech. Bull. Div. Ld Util. Qd Dep. Prim. Inds. No. 14.

Thompson, C.H. and Beckmann, G.G. (1959) - Soils and land use in the Toowoomba area, Darling Downs, Queensland. Soils Ld Use Series CSIRO Aust. No. 28.

Truong, P.N. (1979) - The Ellinbank Pasture Meter - a new method for measuring retardance categories in grassed waterways. Tech. News Div. Ld Util. 3:30-32.

Truong, P.N. and McDowell, M.G. (1980) - Monitoring grass retardance categories in waterways with an Ellinbank Pasture Meter. Tech. News Div. Ld Util. 4:38-42.

USDA (1954) - Handbook of channel design for soil and water conservation. Stillwater Outdoor Hydraulic Laboratory, Stillwater Oklahoma. Soil Conservation Service - TP - 61 Washington D.C.

Vandersee, B.E. (1977) - Field identification of impermeable B horizons of the Marburg Formation soils. Technical News Soil Conservation Darling Downs Region 1:5-6.

Vandersee, B.E. and Mullins, J.A. (1977) - Land evaluation of representative areas of the Marburg Formation and the Poplar Box Walloons of the Eastern Downs Queensland. Tech. Bull. Div. Ld Util. Qd Dep. Prim. Inds. No. 21.

Wischmeier, W.H. and Smith, D.O. (1978) - Predicting rainfall erosion losses - a guide to conservation planning. Agric. Handb. U.S. Dep. Agric. No. 537.

I-i

APPENDIX I

Detailed Soils'

Information for the AMUs of the Basalt East.

Basaltic Red Soils and AI luvium Land Resource Areas

bY

S.E. MACNISH

1. Soils in the relation to the landscaPe

2. Detailed Soil Profile DescriPtions

3. KeY to the AMUs of the Basalt East LRA

4. KeY to the AMUs of the Basaltic Red Soils LRA

I-ii

1. Soils in Relation to the LandscaPe

The soils of the Basalt East and Basaltic Red Soils LRAs are developed on basalts and tuffaceous material respectively. The basalts are of Tertiary age (Miocene-Pliocene). Work presently underway suggests that some of the tuffaceous material may be considerably younger (i.e. late Tertiary - Pleistocene age). The soils of the Alluvium LRA are formed on reworked material from the basalts and tuffs and in some cases mixed with or overlying coarse grained sediments predominantly of the Marburg Formation.

The Basalt East LRA includes all those cracking and noncracking dark clay soils formed on weathered basalt to the east and north east of the Great Dividing Range.

The Basaltic Red Soils LRA includes all those soils, predominantly krasnozems and associated colluvia, which have formed on the old Tertiary plateau surface or on its dissected remnants.

The Alluvium LRA consists largely of infilled trough valleys which interfinger all other LRAs in the district.

The distribution of soils in each of these three LRAs is directly controlled by geology and geomorphic processes. A brief outline of these relationships follows.

(i) Basalt East LRA

The basalts are of Tertiary age similar to the basalts of the Basalt West LRA. Uplift and dissection of the Main Range in this area in more recent times has, however, exposed fresh basalts on which weathering has proceeded for a comparatively shorter time than in the Basalt West LRA. This uplift and the subsequent deep dissection explains the relatively narrow and steep-sided valleys of the Basalt East LRA b y comparison with landforms in the Basalt West LRA. The upper slopes are dominated b y shallow skeletal soils and shallow gravelly clays. There is relatively poor development of colluvial soils in lower slope positions in the Basalt East LRA and valleys are characterised by trough valley infills instead. This indicates a process of rapid valley filling associated with uplift rather than a steady process of slope development by slope retreat and colluviation. In these situations, erosion often is restricted to deep incision of the valley floor, and the short slopes are frequently too steep for extensive agricultural use.

(ii) Basaltic Red Soils LRA

Soils in the Basaltic Red Soils LRA are developed both on deeply weathered basalts and on tuffaceous sediments. The soils formed depend largely on their position in the landscape.

I-iii

Soils on plateau remnants and crests under open eucalypt forest are predominantly 'snuffy' krasnozems. Where these surfaces have been dissected, detrital or reworked ironstone-rich shallow krasnozems (Cabarlah AMU) have developed. Where sufficient colluvial material has collected on this upper dissected plateau surface, moderately deep cracking clays (Merritts AMU) have developed. These often tend to be in poorly drained depressions and may be associated with fluctuating watertables.

The Geham AMU, a xanthozem, is also developed in colluvial material derived largely from material from the Cabarlah and Pechey AMUs. It is associated with a fluctuating watertable and is generally impermeable by a depth of 45 em.

Deep earthy krasnozems (Ravensbourne AMU) dominate the rainforest and eucalypt open forest areas to the east and below the Main Range. These appear to have developed both on deeply weathered basalt and on tuffaceous material;. A shallower krasnozem (Palmtree AMU), which is generally impermeable by a depth of 60 em, occurs mainly in the transitional forest areas. This appears to be developed only on tuffaceous material.

The Pinelands 1 and 2 AMUs form a soil association that is controlled by local geology and have a restricted distribution in the north of the area. Pinelands 2 AMU, is a strongly acid soil which occurs on ridges, plateaux and steep valley sides and is developed on acid tuffaceous material. The Pinelands 1 AMU has developed on weathered basalt on benches in the landscape which occur at lower elevations than Pinelands 2. Pinelands 1 is thus a krasnozem on weathered basalt with colluvial additions of Pinelands 2 soil material.

(iii) Alluvium LRA

The three main alluvial soils are derived from varying rates of mixing of basaltic, tuffaceous and sandstone derived material. Three broad families of soils were defined.

Als AMU - these are strongly structured, self-mulching, cracking, black, clay soils derived predominantly from basaltic material.

Alw AMU - these are soils with crusting, poorly structured surfaces which are derived predominantly from basaltic material but with some Marburg Formation influence.

Alh AMU - these are hardsetting duplex soils which are derived predominantly from Marburg Formation material and have little or no basaltic influence.

I-iv

2. Det a i l ed Soi l Profi l e Des c r i Pt ions

Basalt East Land Resource Area

BSd Site 1

BSs Site 2

BFwd Site 5

BFs Site 6

BFd Site 8

Basaltic Red Soils LRA

Pinelands 2 Site 4

Ravensbourne Site 12

Palm tree Site 13

Pechey Site 15

Pinelands 1 Site 16

Merritts Site 17

Geham Site 18

Cabarlah Site 19

Alluvium LRA

Als Site 9

Alw Site 10

Alh Site 11

I-v


SUe

AGRICULTURAL MANAGEMENT UNIT: BSd

PRINCIPAL PROFILE FORM (Northcote): Ug 5.13

1980 DATE OF DESCRIPTION: 27th February,

LOCATION: Craw's Nest District, Queensland 924 3 1: 100 000 Sheet Number Australian Map Grid Reference 395500E 6987300N

TOPOGRAPHY: Mid to lower slope position (10% land slope) on low, hilly terrain.

PA�ENT HATERIAL: Tertiary basalt.

PROFILE DRAINAGE: Moderately well drained.

VEGETATION: Depauperate rainforest with Flindersia australis (Craw's Ash) and GreviZZea robusta (silky oak) and softwood scrub understorey.

LAND USE: Selectively logged forest.

MORPHOLOGY:

Depth (em)

0 - 2

2 - 10

10 - 25

25 - 40

40 - 70

70 - 80

So - 120

Description

Brownish black (7.5 YR 3/1 moist); self-mulching; medium-heavy clay; weak, very fine crumb; soft (dry). Field pH 6.5. Abrupt to -

Brownish black (7.5 YB 3.1 moist); heavy claymoderate, medium granular; slightly hard (dry} . Field pH 6.8. Clear to -

Brownish black (7.5 YR 3/1 moist); heavy clay; strong, medium granular; hard (dry). Field pH 7.2. Diffuse to -

Dark reddish brown (5 YB 3/2 moist); heavy clay; firm (moist). Trace of calcium carbonate nodules. Field pH 8.2. Diffuse to -

Grayish brown (5 YR 4/2 moist); heavy clay; firm (moist). Trace of calcium carbonate nodules and soft segregations. Field pH 8.5. Diffuse to -

Grayish brown (5 YR 4/2 moist); heavy clay; firm (moist). Small amount of soft calcium carbonate segregations and nodules. Field pH 9.5. Gradual to -

Brown (7.5 YR 4/4 moist); medium clay; friable (moist). Small amount of soft calcium carbonate segregations and basaltic gravel. Field pH 9.5.

I-vi

Sde 2

AGRICULTURAL MANAGEMENT UNIT: BSs

PRINCIPAL PROFILE FORM ( Northcote) : Ug 5.12

DATE OF DESCRIPTION: 27th February, 1980

LOCATION : Craw's Nest District, Queensland 9243 1:100 000 Sheet Number Australian Map Grid Reference 397000E 6991900N

TOPOGRAPHY: Upper convex slope position (15% land slope) on low, hilly terrain.

PARENT HATERIAL: T ertiary basalt.

PROFILE DRAINAGE: Well drained.

VEGETATION: Depauperate rainforest with Flindersia australis (Craw's Ash) and Grevillea robusta (silky oak) and softwood scrub understorey.

LAND USE: Extensive logging and clearing for grazing.

MORPHOLOGY:

Depth (em)

0 - 10

10 - 20

20 - 25

Description

Brownish black (5 YR 3/l moist); self-mulching; light-medium clay; moderate, medium granular; hard (dry). Trace of basaltic gravel. Field pH 7.0. Gradual to -

Brownish black (5 YR 3/1 moist); light-medium clay; moderate, medium granular; hard (dry). Moderate amount of basaltic gravel. Field pH 7.0. Gradual to -

Brownish black (5 YR 3/l moist); light clay. Abundant basaltic gravel. Field pH 6.8.

Sde 5

AGRICULTURAL MANAGEMENT UNIT: BFwd

PRINCIPAL PROFILE FORM ( Northcote) : Ug 5.13


LOCATION: Craw's Nest District, Queensland 9243 1:100 000 Sheet Number Australian Map Grid Reference 379900E 7001200N

TOPOGRAPHY: Mid to lower slope position (6% land slope) on low, hilly terrain.

PARENT MATERIAL: Tertiary basalt.


VEGETATION: Open woodland of Eucalyptus crebra (narrow-leaved ironbark) (cleared).

LAND USE: Summer and winter dryland cropping.

MORPHOLOGY:

Depth (em)

0 - 10

10 - 20

20 - 35

35 - 75

75 - 90

I-vii

Description

Black (7.5 YR 2/l moist); self-mulching; light clay; weak, very fine crumb; soft (dry), very friable (moist). Trace of basaltic gravel. Field pH 6.5. Gradual to -

Black (7 .5 YR 2/l moist); light clay; weak, very fine crumb; soft (dry), friable (moist). Field pH 6. 8. Gradual to -

Dark reddish brown (5 YR 3/3 moist); lightmedium clay; weak, very fine blocky; soft (dry), friable (moist). Field pH 7.0. Gradual to -

Dark reddish brown (5 YR 3/4 moist); medium clay; firm (moist). Field pH 7.0. Clear to -

Brown (7.5 YR 4/4 moist); medium clay; firm (moist). Moderate amount of basaltic gravel. Field pH 7.0.

Site 6

AGRICULTURAL MANAGEMENT UNIT: BFs


1980 DATE OF DESCRIPTION: 27th February,

LOCATION: Crow's Nest District, Queensland 9243 1:100 000 Sheet Number Australian Map Grid Reference 379500E 7001500N

TOPOGRAPHY: Crest (3% land slope) on low, hilly terrain.



VEGETATION:

LAND USE:

MORPHOLOGY:

Depth (em)

0 - 10

10 - 20

Grassy open woodland of Eucalyptus crebra (narrowleaved ironbark), some Eucalyptus ter-8tieornis (Queensland blue gum) and scattered shrubs.

Selectively logged for grazing.

Description

Black (7.5 YR 2/l moist); self-mulching; medium clay; weak, medium granular; slightly hard (dry) , friable (moist). Small amount of basaltic gravel. Field pH 6.8. Gradual to -

Black ( 7. 5 YR 2/1 moist) ; medium clay; medium granular; slightly hard (dry). basaltic gravel. Field pH 7.0.

moderate, Abundant

I-viii

SUe_ g

AGRICULTURAL MANAGEMENT UNIT: BFd

PRINCIPAL PROFILE FORM (Northcote) : Ug 5.13

DATE OF DESCRIPTION: 29th April, 1980

LOCATION:

TOPOGRAPHY:

Craw's Nest District, Queensland 9243 1:100 000 Sheet Number Australian Map Grid Reference 388400E 6999800N

Mid to lower slope (7% land slope) on moderately undulating terrain.



VEGETATION: Eucalypt open woodland (cleared).

LAND USE: Summer and winter dryland cropping.

MORPHOLOGY:

Depth (em)

0 - 10

10 - 35

35 - 50

50 - 90

90 - 100

100 - 120

Black (10 YR heavy clay; hard (dry).

Description

2/1 moist); self-mulching; mediumstrong, fine granular; slightly

Field pH 6.8. Clear to -

Black (10 YR 2/1 moist); heavy clay; moderate, fine blocky; firm (moist). Field pH 6.8. Gradual to -

Brownish black (10 YR 2/2 moist) with a few black mottles; heavy clay; friable (moist). Field pH 7.0. Diffuse to -

Brownish black (10 YR 3/2 moist) with a few black mottles; heavy clay; friable (moist). Field pH 7.5. Diffuse to -

Dark brown ( 10 firm (moist). Field pH 8. 5.

YR 3/3 moist); light-medium clay; Small amount of basaltic gravel. Clear to -

Brown (7.5 YR 4/4 moist); light clay; very friable (moist). Moderate amount of basaltic gravel and calcium carbonate nodules. Field pH 9.0.

I-ix

BASALTIC RED SOILS LAN D RESOURCE AREA

��r sae 4

AGRICULTURAL MANAGEMENT UNIT: Pinelands 2

PRINCIPAL PROFILE FORM (Northcote): Gn 4.11



TOPOGRAPHY: Upper slope position (8% land slope) on low, hilly terrain.



VEGETATION:

LAND USE:

MORPHOLOGY:

Depth (em)

0 - 8

8 - 15

15 - 20

20 - 30

30 - 100

Softwood scrub.

Virgin scrub.

Description

Dull reddish brown (2.5 YR 4/3 moist); loosesurfaced; light clay; weak, very fine crumb; slightly hard (dry). Field pH 5.0. Clear to -

Dull reddish brown (2 .5 YR 4/3 moist); lightmedium clay; weak, very fine blocky; slightly hard (dry). Field pH 5.0. Diffuse to -

Dull reddish brown (2.5 YR 4/3 moist); mediumheavy clay; weak, very fine blocky; slightly hard (dry). Field pH 4.5. Diffuse to -

Dull reddish brown (2.5 YR 4/4 moist); mediumheavy clay. Field pH 4.5. Diffuse to -

Dull reddish brown (2.5 YR 4/4 moist); mediumheavy clay. Trace of tuffaceous and basaltic gravel. Field pH 4.0.

S.Ue 12

AGRICULTURAL MANAGEMENT UNIT: Ravens bourne


DATE OF DESCRIPTION: 18th September, 1980

LOCATION: Craw's Nest District, Queensland 9343 1:100 000 Sheet Number Australian Map Grid Reference 41T850E 69T2TOON

TOPOGRAPHY: Crest (1% land slope) of broad convex ridge.


c

I-x

PROFILE DRAINAGE: Very well drained (somewhat excessive).

VEGETATION: Rainforest.

LAND USE: Virgin rainforest.

MORPHOLOGY:

Depth (em) Deseription

0 - 10 Brownish black ( 5 YR 2/2 moist); loose-surfaced; clay loam; weak, fine crumb; loose (moist). Field pH 6.0. Gradual to -

10 - 18 Brownish black ( 5 YR 2/2 moist); clay loam; weak, fine crumb; very friable (moist), soft (dry). Field pH 5.8. Gradual to -

18 - 35 Dark reddish brown (2.5 YR 3/3 moist); light clay; moderate, very fine blocky; slightly hard (dry). Field pH 5.8. Diffuse to -

35 - 90 Dark reddish brown (2.5 YR 3/4 moist); lightmedium clay. Field pH 5.5. Diffuse to -

90 - 120 Dark reddish brown (2.5 YR 3/4 moist); lightmedium clay. Field pH 5.2.

SM:e 73

AGRICULTURAL MANAGEMENT UNIT: Palmtree




TOPOGRAPHY: Upper convex slope on low hilly terrain (3% land slope).


PROFILE DRAINAGE: Moderately well drained; impermeable deep subsoil.

VEGETATION:

LAND USE:

MORPHOLOGY:

Depth (em)

0 - 10

10 - 35

35 - 65

Layered rainforest transitional to Eucalypt open forest.

Selective logging.

Deseription

Brownish black (5 YR 2/2 moist); loose-surfaced (with litter); light clay; weak, medium granular; slightly hard (dry). Field pH 6.0. Diffuse to -

Brownish black (5 YR 2/2 moist); light-medium clay; weak, medium granular; slightly hard (dry). Field pH 6.0. Gradual to -

Dull reddish brown (2.5 YR 4/4 moist); medium-heavy clay; moderate, fine blocky; hard (dry). Field pH 5.8. Diffuse to -

MORPHOLOGY

Depth (em)

65 - 90

90 - 120

(CONT. ) :

I-xi

Description

Reddish brown (5 YR 4/6 moist); heavy clay; hard (dry). Trace of basaltic gravel. Field pH 5.5. Diffuse to -

Reddish brown (5 YR 4/6 moist); heavy clay; hard (dry). Trace of basal tic gravel. Field pH 5. 3.

S-Ue 15

AGRICULTURAL MANAGEMENT UNIT: Pechey

PRINCIPAL PROFILE FORM (Northcote) : Gn 4.12


LOCATION:

TOPOGRAPHY:

Grow's Nest District, Queensland 9343 1:100 000 Sheet Number Australian Map Grid Reference 408200E 69T8700N

Extensive plateau surface (3% land slope).



VEGETATION: Grassland, mainly Paspalum dilatatum (paspalum) and Imperata cylindrica (blady grass).

LAND USE:

MORPHOLOGY:

Depth (em)

0 - 10

10 - 20

20 - 35

35 - 95

95 - 120

Cleared for grazing.

Description

Brownish black (5 YR 2/2 moist); snuffy loam; structureless; loose (dry). Field pH 6.8. Gradual to -

Very dark reddish brown (5 YR 2/3 moist); clay loam; structureless; loose (dry). Field pH 6.5. Clear to -

Dull reddish brown (2.5 YR 4/4 moist); light clay; weak, very fine blocky; soft (dry). Small amount of ironstone and basaltic gravel. Field pH 6.0. Diffuse to -

Reddish brown (2.5 YR 4/6 moist); clay; slightly hard (dry). Small ironstone gravel. Field pH 6.0.

light-medium amount of Diffuse to

Bright brown (T.5 YR 5/6 moist); light-medium clay; slightly hard (dry). Small amount of ironstone gravel. Field pH 6. 8. ·

I-xii

SUe. 16

AGRICULTURAL MANAGEMENT UNIT: Pinelands 1




TOPOGRAPHY: Crest (2% land slope) on low hilly terrain.



VEGETATION: Softwood scrub (cleared), now kikuyu grassland.

LAND USE:

MORPHOLOGY:

Depth (ern)

0 - 10

10 - 20

20 - 40

40 +

Cleared for grazing.

Description

Very dark reddish brown ( 5 YR 2/3 moist); loosesurfaced; light clay; weak, medium granular; slightly hard (dry). Field pH 6.8. Clear to -

Dark reddish brown (5 YR 3/4 moist); light clay; weak, fine blocky; slightly hard (dry). Trace of lateritic gravel. Field pH 7.0. Diffuse to -

Dark reddish brown (5 YR 3/4 moist); light clay; soft (dry). Small amount of lateritic and basaltic gravel. Field pH 7.0. Gradual to -

Weathered basalt and basaltic gravel.

SUe. 17

AGRICULTURAL MANAGEMENT UNIT: Merritts




TOPOGRAPHY: Saddle of dissected plateau (1% land slope).

PARENT MATERIAL: Tertiary basalts.


VEGETATION: Eucalypt open woodland (cleared).

LAND USE: Dryland grain cropping.

MORPHOLOGY:

Depth (em)

0 - 10

10 - 22

22 - 50

50 - 78

78 - 90

90 - 105

105 +

I-xiii

Description

Brownish black (10 YR 2/2 moist); self-mulching; medium clay; moderate, medium granular; hard (dry). Field pH 5.8. Clear to -

Black ( 10 YR 2/1 moist); medium clay; moderate, fine blocky; firm (moist). Field pH 6.0. Gradual to -

Dark brown (10 YR 3/4 moist); medium-heavy clay; blocky; firm (moist). Trace of lateritic gravel. Field pH 6.5. Diffuse to -

Brown (7.5 YR 4/3 moist); medium clay; lenticular; firm (moist). Trace of lateritic gravel. Field pH 6.8. Diffuse to -

Dull brown (7.5 YR 5/4 moist); medium clay; friable (moist). Trace of lateritic gravel. Field pH 6.8. Diffuse to -

Dull yellowish brown (10 YR 5/4 moist); medium clay; friable (moist). Field pH 6.8.

Weathered basalt.

SUe 18

AGRICULTURAL MANAGEMENT UNIT: Geham

PRINCIPAL PROFILE FORM (Northcote): Uf 6.12


LOCATION:

TOPOGRAPHY:

Grow's Nest District, Queensland 9343 1:100 000 Sheet Number Australian Map Grid Reference 403000E 6969300N

Mid slope position (3% land slope) on plains of moderate relief.


PROFILE DRAINAGE: Poorly drained; perched watertable frequently occurs

VEGETATION: Grassy open woodland of Eucalyptus tereticornis (Queensland blue gum).

LAND USE: Extensively cleared for grazing.

MORPHOLOGY:

Depth (em)

0 - 10

10 - 22

Descr>iption

Very dark brown (7.5 YR 2/3 moist); loose-surfaced; light-medium clay; weak, fine granular; slightly hard (dry). Small amount of ironstone gravel. Field pH 6.5. Gradual to -

Very dark brown (7.5 YR 2/3 moist); light-medium clay; moderate, fine granular; slightly hard (dry). Small amount of ironstone and basaltic gravel. Field pH 6.5. Clear to -

(�. - .

I-xiv

MORPHOLOGY (CO�T) :

Depth (em}

22 - 40

40 - 80

80 - 90

90 - 120

Description

Brown (7.5 YR 4/4 moist); medium clay; moderate, very fine blocky; friable (moist). Moderate amount of ironstone and basaltic gravel. Field pH 5.5. Diffuse to -

Reddish brown (5 YR 4/6 moist); medium clay; friable (moist). Small amount of ironstone gravel. Field pH 5.5. Diffuse to -

Brown (7.5 YR 4/6 moist) with common reddish brown mottles; medium-heavy clay; firm (moist). Field pH 5.5. Diffuse to -

Brown (10 YR 4/6 moist) with common reddish brown mottles; medium-heavy clay; firm (moist). Field pH 5.5.

S-Ue. 79

AGRICULTURAL MANAGEMENT UNIT: Cabarlah

PRINCIPAL PROFILE FORM

DATE OF DESCRIPTION:

(Northcote) : Urn 6.24

25th September, 1980

LOCATION:

TOPOGRAPHY:

Grow's Nest District, Queensland 9243 1:100 000 Sheet Number Australian Map Grid Reference 398800E 6964600N

Crest (1% land slope) of broad flat ridge.

PARE�T MATERIAL: Tertiary basalt.


VEGETATION: E ucalypt grassy open woodland.

LAND USE: Partially cleared for grazing of native pastures.

MORPHOLOGY:

Depth (em}

0 - 10

10 - 20

20 - 35

Description

Very dark reddish brown (5 YR 2/3 moist); clay loam; weak, very fine crumb; soft (dry). Small amount of ironstone gravel. Field pH 6.5. Gradual to -

Very dark reddish brown (5 YR 2/4 moist); clay loam; weak, very fine granular; soft (dry). Moderate amount of ironstone gravel. Field pH 6.5. Gradual to -

Very dark reddish brown (5 YR 2/4 moist); clay loam; soft (dry). Abundant ironstone gravel. Field pH 6.8.

I-xv


Sili 9

AGRICULTURAL MANAGEMENT UNIT: Als



LOCATION:

TOPOGRAPHY:

Crew's Nest District, Queensland 9243 1:100 000 Sheet Number Australian Map Grid Reference 3925 00E 6991700N

Floodplain (1% land slope).

PARENT MATERIAL: Alluvium, predominantly of basaltic origin.


VEGETATION: Eucalypt grassy open woodland (cleared).


MORPHOLOGY:

Depth (am) Description

0 - 10 Brownish gray (10 YR 4/l moist); self-mulching; heavy clay; strong, fine blocky; very hard (dry). Field pH 6.8. Clear to -

10 - 20 Brownish gray (10 YR 4/l mois�; heavy clay; strong, medium blocky; firm (moist). Field pH 7.0. Gradual to -

20 - 30 Brownish gray (10 YR 4/1 moist); heavy clay; very firm (moist). Field pH 7.8. Diffuse to -

30- 60 Brownish gray (10 YR 4/1 moist); heavy clay; very firm (moist). Field pH 8.5. Diffuse to -

60 - 90

90 - 120

120 - 150

Brownish gray (10 YR 4/1 moist); heavy clay; very firm (moist). Trace of soft calcium carbonate segregations. Field pH 9.5. Diffuse to -

Grayish yellow brown (10 YR 4/2 moist); heavy clay; firm (moist). Trace of soft calcium carbonate segregations. Field pH 9.5. Diffuse to -

Grayish yellow brown (10 YR 4/2 moist); heavy clay; friable (moist). Trace of soft calcium carbonate segregations. Field pH 9.5 .

I-xvi

�e 10

AGRICULTURAL MANAGEMENT UNIT: Alw

PRINCIPAL PROFILE FORM (Northcote): Ug 5. 15



TOPOGRAPHY: Floodplain (2% land slope).

PARENT MATERIAL: Alluvium, predominantly of basaltic and lateritic origin.




MORPHOLOGY:

Depth (em)

0 - 10

10 - 20

20 - 30

30 - 60

60 - 90

90 - 150

Description

Brownish black (7.5 YR 3/2 moist); surface crust lightmedium clay; weak, fine crumb; soft (dry). Field pH 6. 5. Abrupt to -

Brownish black (7 . 5 YR 3/2 moist); heavy clay; moderate, fine blocky; firm (moist). Field pH 6. 8. Gradual to -

Brown (7. 5 YR 4/3 moist); heavy clay; moderate, fine blocky; firm (moist). Field pH 7. 0. Diffuse to -

Brown ( 7. 5 YR 4/4 moist); heavy clay; firm (moist). Field pH 8. 0. Diffuse to -

Brown (7. 5 YR 4/4 moist); heavy clay; friable (moist). Trace of calcium carbonate nodules. Field pH 8. 8. Gradual to -

Brown (7. 5 YR 4/4 moist); medium clay; friable (moist). Trace of calcium carbonate nodules. Field pH 9. 0.

S.{;te 1 1

AGRICULTURAL MANAGEMENT UNIT: Alh

PRINCIPAL PROFILE FORM (Northcote): Db 1. 13


LOCATION:

TOPOGRAPHY:

Crow's Nest District, Queensland 9243 1:100 000 Sheet Number Australian Map Grid R eference 393500E 6994300N

Floodplain ( 1% land slope) .

PARENT MATERIAL: Alluvium, predominantly sandstone origin.

PROFILE DRAINAGE: Imperfect.

I-xvii



MORPHOLOGY:

Depth (em) Description

0 - 10 Brownish black ( 7. 5 YR 3/2 moist) ; hardsetting; sandy clay loam; structureless, massive; hard (dry). Field pH 5. 8. Gradual to -

10 - 20 Brownish black (7.5 YR 3/2 moist); sandy clay loam; structure less, massive; hard (dry). Field pH 5.8. Abrupt to -

20 - 30 Dark brown ( 7. 5 YR 3/3 moist); sandy clay; moderate, coarse blocky; very hard (dry). Field pH 6.0. Diffuse to -

30 - 60 Dark brown (7.5 YR 3/3 moist); medium-heavy clay; moderate, coarse blocky; very hard (dry). Field pH 7.8.

Basalt East LRA

Soils < 45 em deep

Soils > 45 em deep

3. KeY to the AMU s of t he Ba s a l t Ea s t LRA

Brownish black clay loam to light clay over brown to yellowish brown light to medium clay with gravels by 45 em, Occurs on ridges and upper slopes in softwood scrub areas • . . . . . o • o • o o . 0 • • • • • • • • • • • • • • o • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • BSs

Brownish black clay loam to medium clay, uniform colour throughout; gravels and small stone throughout but increasing with depth. Occurs on ridges and slopes in forest areas . . . • . . . . . . . . . . o • • • • • • • • • • o • • • • o • • • • • • • • 0 • • • • • • • o • • • • • • • o • • • • • • • • o • • • • • • • • • • • BFs

Narrow valleys with s hort, steep pediments; softwood scrub with some eucalypts.

Broad valleys with long, low gradient pediments; eucalypt open forest and grassy open wo odland.

Brownish black, weakly cracking medium to heavy clay, fine granular surface grading to blocky dark reddish-brown heavy clay; carbonate by

50 em; non-gilgaied; occurs on lower slopes and valley floors . ................................ BSd

Brownish black, cracking heavy clay, strong granular surface over yellowish brown medium clay with carbonate increasing below 45 em; generally > 1m deep on mid to lower slopes.

Brownish black light clay, weak fine crumb to structureless surface over weak blocky, dark reddish brown subsoil. No carbonate present; only weakly cracking in virgin condition but cracks more strongly with cultivation and loss

BFd

of Al horizon • . . . . . . . . . . . . . 0 • • • • • • • • • • • • • • • o . . . . . . BFwd

B<Jsal tic Red Soils m

I-xix

4. KeY to AMUs of the :Sasalti� Red Soils LRA { Crack1ng clay -- Self mulch1ng med1um to heavy clay, moderate granular surface over brown !llEldlum to heavy clay ;nth rounded basalt and lat<Hltlc gravels, over mottled brown and y<allmush brown med1um

Browno_sh black clay; pH ac1d to neutral throughout, poor to b1ack gu/Jsoil penneal>1lity CoU,w1al soli der1ved gurfac<a so1l from Pechey AMlJ and basaLt1c mater:1al. . ...... , .. . .. .

Non-Crack1ng Weak granular, occas1onally hardseteing surface, clay ironstone and laterite gtavels in dark A

horizon overlying reddish to yellowish brown light to medium clay gra<ling to mottled brown, yellowish brown and grey medium to heavy clay, impermeable subsoil; pH neutral to slightly acid; colluvial soil formed chiefly from Pechey and Cabarlah AMOs, .

Structureless Reddish brown to bright brown light snuffy surface-- to me.dium clay fine blocky subsoil

with increasing amounts of ironstone Loam to clay and laterite gravels, some Mn nodules; loam surface plat"-aux and dissect"d plateaux

remnants. Associated with eucalypt open forest............................ PECHEY

Dark r<:lddish brown to reddisll brown surfac<:l soil

Light clay surface

Fine crumb to < 35 em de"p to -- Reddish brown loam to clay loam

surface latei:ite gravels clay Increas1ng amounts of or rnass1ve 1ronstone and later1te gravel later1te overly1ng hard to mass1ve latente,

occurs on r1dges and plateaux remnants Assoc1ated with eucalypt open forest. . . . . . . . . . . . . . . CABARLAH

> 35 em deep -- Fme blocky red to reddish brown light clay subsoil with increasing amounts of laterite gravels; > 150 d"-ep 8l>d may be many metres deep; slightly acid throughout; fr"ely drai.ning; occurs on plateaux and 3teep slopes. Associated with rainforest. . . • . . . • . . . . . . . . . . RAVENSBOURNE

Developed. an Gunular to fine blot.ky surfat.e weath"red --- ovar reddish brown. blocky light basalt to mfodium clay with basalt gravel

and floaters; pH neutral throughout; some lateritic gravels; occurs on benches and plateaux remnants generally below Pinelands 2 AMU. Asso<::iated with softwood scrub.

Developed on laterite or tuffaceous

material

Structureless surface with no dark organic A horizon over fine blocky light to medium clay of dull reddish brown to yellowish red colour; pH 3.5 � 5.0 throughout; occurs on plato;aux and steep slopes associated with Pinelands 1 AMU. Associated <->ith softwood scrub . . . . . . . . • . . .

Moderate granular surface over brown to rfoddish bro<->n fine blocky medium clay ov"r rrroeel"d reddish ra yellowish brown. medium clay; JOOderately impermeable by 100 em; pH 6.5 throughout; occurs on slopes and low ridg"'S. Associated with eucalypt forest/softwood scrub areas ...

PINELAND$ l

PINELANDS 2

II-i

APPE NDIX II

Soi l Ana l Yt i c a l Da t a for R ePrese n t at i v e Profi l es

of the Basa l t Eas t , Basa l t i c Red

Soi l s and A l l uvium Land Resource Area·s

b Y

S.E. Mac nlsh

Land Resourc� Area

� RED

SOILS

Agricultural Hanagement Unit

1:100 000 Topogr-aphic Sheet and Grid P.ehrence

"� 9243

397000E 6991900N

""

9243

395500� 6987300N

Bfs 9243

3795008 7001500N

""

9243

388400E 6999800N

BFwd

9243

379900E 7091200N

CAOARLA<J

9243

398800E 6964600N

fEC<iEY

9343

408200E 69'/8700N

GEHil'1

9343

403000E 6969300K

RAVENSBOURN3

9343

417850E 6972700N

PALI-ITREE

9343

4192008 69'15700N

PINELANDS

9243

3973008 6989600N

Depth (c:nl

0-10 7.2

10-20

20-25

'( .3

u

O-lD 6.5

10-20

20-30 6.9

50-60 8.3

so-go 8.4

0-10

10-20

0-10

10-20

20-30

50-60

80-90

0-10

10-20

20-30

50-&0

0-10

10-20

20-30

0-10

10-20

20-30

50-60

80-90

'·' '·' ;.; o.o

9.9

'·' "-'

110-120 6.4

0-10

10-20

20-30

50-60

80-90

'·' '·' '·' ;.o '·'

110-120 5.4

0-10

10-20

20-30

50-60

80-90

110-120 5.3

0-10

10-20

20-30

50-60

80-90

5.8

110-120 5.3

0-10

10-20

20-30

'·' '·' '·'

Electr�cal Conduct�vity 1:5 E221 lmS.c" I

0.06

0.08

0.03

0.05

0.06

0.10

0.45

0.68

0.09

0.05

0.32

C.OS

0.10

0.07

0.29

0.08

0,05

0.05

0.03

0.07

0.05

0.03

0.07

0.03

0.02

0.02

0.02

0.02

0.05

0.05

0.03

0.02

0.06

0.15

0.11

0.06

0.05

0.03

0.03

0.03

0.07

0.07

0.�

0.03

0.03

0.02

0.18

0.13

0.11

II-ii

ANALYTICAL DATA FOR R2PR2SEI�TATIVE SOIL PRO?IL£.3 FOR Tli� CRO!.J'S �fSfDISTRICT

Chlnnde '"

0.004

0.006

0.002

0.008

0.003

0.013

0.060

a. roz

0.004

0.005

0.002

0.002

0.002

9.005

0.0�5

0.002

0.001

0.001

0.001

0.004

0.003

0.002

0.004

0.003

0.002

0.001

0.()01

0.003

0.002

0.002

0.003

0.005

o.oos 0.019

0.004

0.004

0.004

0.005

0.006

0.005

0.006

0.005

0.003

O.OQJ

0.005

0.004

0.007

0.006

0.005

11oisture Percentae;e

14.1

12.9

15.6

'·'

11.2

11.0

13.6

15.7

15.0

9.;

10.6

'·'

'·' 5.5

0.9 _3.1

o.;

11.3

12.9

'·' ;.o '·'

'·'

1/3 Bar 15 Bar

,,,

Or�J:an�c Carbon

1%1

2.4

Total N1trogen

1%1

0.26

0.1'<

0.1,7

0.26

0.22

0.20

0.26

0.13

0.42

0.30

0.16

0.10

0.55

0.36

0.50

0.43

0.50

0.37

Total PhosphorUB

(%)

0.174

0.129

0.137

0.275

O.Og4

0.047

0.038

0.318

0.319

0.302

0.086

0.074

0.131

0.086

0.062

0.062

0.056

0.079

0.052

0.041

0.022

0.016

0.140

0.201

0.197

0.135

0.120

0.138

0.101

Total Potass1um

'"

1.06

0.91

1.15

0.82

0.80

1.02

1.05

0.30

0.32

0.24

o.n

2.41

1.83

1.45

o.os

0.06

0.25

0.09

0.09

0.05

0 .. 02

0.15

0.08

0.68

0.05

0.05

0.21

0.13

0.09

0.06

0.03

0.08

0.03

0.02

0.01

0.01

'·'

'·'

Total Sulphu�

"'

0.038

0.017

0.053

0.023

0.021

0.021

0.050

0.033

0.024

0.015

0.012

O.C3?

0.026

0.01?

0.059

0.041

0.064

0.040

0.018

0.026

0.021

0.040

0.027

0.013

0.008

0.005

0.088

0.048

0.032

0.036

0.048

0.079

0.051

0.035

0.04'<

0.052

0.072

0.042

�" Resource MM

� � SOILS

AgriculWral 11anageroent Unit

1!100 000 To�ogr-aphic Sheet and Grid Reference

fitfELANDS

9243

397400E 6987500N

MERRIITS 9243

404100E 6973000N

'� 9243

393500E 6994300N

!'.Lll 9243

393400E 6994700N

.JILS

9243

392500E 6991700N

�pth [em)

0-10

10-20

20-30

50-60

0-10

10-20

20-30

50-60

80-90

0-10

10-20

20-30

50-60

0�10

10-20

20�30

50-60

30-90

0-10

10-20

20-30

50-60

80-90

110-120

140-150

" 1:5

"'

electrical Conductivity

1.;1.�Q1)

0.03

0.03

C.OJ

0.15

0.24

0.14

0.10

0.07

0.09

0."07

0.06

0.08

0.24

0.06

0.06

0.06

0.23

0. 70

0.13

0.11

0.12

0.16

0.23

0.32

0.53

II-i:�

Chloride "'

0.002

0.003

0.001

0.013

0.004

0.004

0.004

0.005

0.003

0.004

0.004

0.006

0.026

0.003

0.002

0,003

0.032

0.107

0.003

0.003

0.003

0.005

0.004

0.018

0.066

1-loisture �ercentage

10.6

11.6

14.3

'·'

'·" 11.0

11.5

'-' '·'

113 Bar 15 Bar

"

Organic carbon

1%)

'·" u

To tel Nitr<>.gen

"'

0.22

0.16

0.62

0.41

o.n 0.13

0.17

0.15

0.16

0.12

Total l't:tosphorus

1%1

0.294

0.207

0.179

0.138

0.063

0.033

0.070

0.167

0.184

0.125

0.170

0.117

0.100

0.136

0.078

0.057

0.065

0.081

0.100

0.107

Total Potasswm

1%1

0.09

0.04

0.02

0.64

0.52

0.24

0.61

1.13

o.n 0.93

1.05

0.90

0.82

0.96

0.90

0. 75

0.91

0.92

0.95

u

Total Sulphur

1%)

0.031

0.037

0.096

0.029

0.017

0.033

0.027

0.014

0.015

0.026

0.018

0.013

0.011

0.023

0.017

0.015

0.012

0.010

0.009

Land

� '" SOIL.$

Ag<'i<:ultur�l Hanagement Un1t 1:100 000 topograph1c Sheet and Grict Reference

9243 397000E 69919GGN

= 9243

395500E 69373001/

'" 9243

379500E 70015001/

"' 9243

3884002 69998001/

BFwd

9243 379900E 70912001/

CABARLAH

9243 398800E 696460011

PECHEY 9343

408200E 697870011

GEHAfl 9343

403000E 696930011

RAVIDISBOURNE 9343

4178508 697270011

PALHTREE 9343

4192008 6975700N

PIIIELANDS

9243 397300E 698960011

Depth (em)

0-10 10-20 20-25

0-10 10-20 20-30 50-60 80-90

0-W 10-20

0-10 10-20 20-30 50-60 80-90

0-W 10-20 20-30 50-60

0-10 10-20 20-30 50-60 80-90

110-120

0-10 10-20 20-30 50-60 80-90

110-120

0-10 10-20 20-30 50-60 80-90

110-120

0-10 10-20 20-30 50-60 80-90

110-120

0-10 10-20 2()-10

ANALYTICilL DATA FOR R�PRES�NTATIV� SOIL P�OFILES �OR THE CRQ)/S N�ST lllSTRlCT

Part�cle Size Distribution '"

Coarse Fine Sand Sand Silt Clay

Exchangeable ;:ations lm eq. 100g- )

(.(

6.6 0.1

9.9 0.3

0.25

0.12

0.32

0.24 0.24 0.20

0.60

0.30

0. 7D

0.37 0.41

4.2 0.35 U.23

4.1 0.30 0.09

7.5 0.40 2.0

6.0 0.45 0.20

1.8 5.2 0.45 0.08 1.1 4.6 0.50 0.05 0.88 4.3 0.30 0.03

6.9 D.JO 0.34

5.8 0.35 0.08

7.7 0.45 0.03 9.5 0.6C 0.03

0.04

7.0 0.55 0.39

5.1 0.50 0.10 0.28 4. 7 0.45 0.04

0.57 4.5 0.45 0.03

0.45 3.4 0.40 0.03

6.1 0. 70 0.27

4.3 0.60 0.05

2.1 3.1 0.45 <0.03

1.1 2.6 0.30 <0.03

0.62 2.5 0.30 <0.03

4.1 0.25 4.0

2,1 ().25 2,7

Cation Exchange Capacity lm eq. lOOg-1)

Exchar>.geaOle Sodium Percentage

0.39

0.57

0.53

0.68

0. 71

0.26

0.70 '.;

1.25

0.96

1.25

Extractable Phosphorus {ppm)

Acid Bicarb

"'' 1950

1250 1375

130

Replaceable Potassiurn (m eq. 100g-1)

0.39 0.19

'-' 0. 78

0.48 0.25

u 0.60

0.27

o.n

Lo O.M

0.35 0.17

0.38 0.19

0.28 0.17

,_, '·'

� RED

SOILS

Auicul tural Hanagernent Unit 1:100 000 To�ographic Sheet and Grid Reference

nNELANDS

9243

397400E 6987500N

l1ERRITTS

9243

404100E 6973000N

·� 9243

393500E 6994300N

ALW 9243

393400E 6994700N

''"'

9243

3925008 6991700N

Depth lro>

0-10

10-20

20-30

50-60

0-10

10-20

20-30

50-60

80-90

0-10

10-20

20-30

50-60

0-10

10-20

20-30

50-60

S0-90

0-10

10-20

20-30

50-60

8\1-90

110-120

140-150

II-v

farticle Size D�stribution '"

Coarse """

Fine '�'

"

Silt Clay

Exchangeable Catio"" {m eq. 100g-l)

1.2 0.20 0.20

0.69 0.36 0.15 0.07

0.35 0.47 0.35 0.07

0.45 2.8

0.90 1.5

'"' ,_,

0.39

0.17

3.8 <0,1 '"'

9.4 38

s.s 36

o.; '"'

'"' '·' 3.4

0.�

0.45

0.&

0.53

0.23

0.24

0.62

0.42

0.44

0.52

0.55

cation Exchange capacity

(rn eq, 100g-11

=�allle �'Percentage

0.80

<0.5

Extractable Pllosphorus (ppm)

Acid Blcarb

"' '"

Replaceallle Potassium

(rn eq. 100g-1J

0.19

0.12

'-' o. 75

0.65

0.50

0.70

0.45

TYPE OF LIMITATION

FACTORS LIMITING CHOICE OF CROPS OR CROP PRODUCTIVITY

FACTORS LIMITING THE USE OF AGRICULTURAL MACHINERY

FACTORS CONTROLLING LAND DETERIORATION

III-i

APPENDIX III

Land CaPab i l i t Y C l ass i f i c at i o n f o r A�r i c u l ture

< af t er R o sser et a l 1974>

LIMITING FACTOR Climatic limitation other than rainfall ''C''

Moisture availabili!}' for crop growth "rh'

Effective soil depth "d"

Soi I physical factors affecting crop growth "p"

Soil nutrient fertility ''n''

Soil salinity or sodicity ''s''

Topography "t"

Soit workability "k"

Rockiness or stoniness "r"

Surface microrelief oilaai and gullying "'g"'

Wetness ''w''

Susceptibility to water' erosion "e"

Susceptibility to flooding "f�' ·

Susceptibility to wind erosion ''a''

DEGREE OF LIMITATION Slight restriction to choice of crops or slightly restricted production potential.

Moderate restriction to choice of crops or moderately restricted production potential. Severely restricted choice of crops and severely reduced production potential. Climatic limitation too severe to allow cropping. Occasional limitation to crop production; 7-8 crops possible in 10 years Re�lar limitation to crop production; 5-7 crops possible in 10 years. Occasional cro�ping possible. Less than 5 crops possible in 10 years. Water availability too unreliable to allow cropping. Effective soil depth so-100 em Effective soil depth 45-60 em Effective soi I depth 25-45 em Effective soi I depth .C. 25 em

SUB-CLASS C2 C3 C4 C6

m2 m3 m4 m6

d2 d3 d4 d6

Degree of limitation imposed on crop production from soi I physical factors affecting the growth of crop plants e.g. surface crusting, hard pans, cementation etc.

Slight restriction. p2 Moderate restriction p3 Severe restriction. p4:

Moderate deiiciencies which Tr'fa'/ be economica\ly corrected with care1ul management.. _ Severe defiCiencies. difficult to correct and which require special management practices. Very lOIN fertility; continuous cultivation precluded by structural decline. Soil water availability slightly restricted or sli!tlt structure decay affecting crop production. Soil water availability moderately restricted or moderate structural decay with some toxic effect on crops. Soil water availability severely restricted or severe structural decay with moderate to severe toxicity. Salinity or alkalinity too severe for crops. Tolerant improved species available. Salinity or alkalinity too severe for pasture improvement; tolerant herbage available. Bare salt pan; not practical to vegetate.

Severe relief or major gullies preclude contour cultivation. Occasional cropping possible. Slopes 15-20% or severe relief or gullying preventing cultivation. Slopes 20-45% or extreme gullying but accessible to grazing animals. Slopes on topography too severe for grazing animals.

n2 n3 n4 s2 s3 s4 s6 s7 ss

t4 t6 t7 t8

Soi I properties affecting machinery and thus reducing average production potential e.g., stiff clay, columnar structure, compaction, narrow moisture range for

Slight restric- 1<.2. tion.

working. ·. Moderate restriction k3 Severe restriction. k4

Tillage restricted with some types of machinery. Tillage restricted with most types of machinery. Tillage difficult with all machinery; occasional use possible. Use of all machinery tor cropping impractical. Tillage restricted with some types of machinery. Ti 1\age restricted with most types of machinery. Tillage difficult with all machinery; occasional use possible. Use of aH machinery for Cf()pping impractical. use of implements detayed occasionally and slightly reduced production �tentia.l. · � · -- . Use of implements delayed reQularly and moderately reduced Production potential. Use of implements very difficult and occasional crops only possible. Pelll13:nently wet; use for cultivation impractical.

Simple practices required to reduce water erosion under cultivation to the acceptable level. Intensive practices reQuired to reduce water erosion under cultivation to the acceptable level. ReQuires inclusion of a pasture phase to reduce average water erosion tosses to the acceptable level. Continuous pasture required to reduce water erosion losses to the acceptable level. Special practices or grazing restrictions required to reduce water erosion losses to the acceptaDte level. Under grazing water erosion losses are in excess of the acceptable level, Subject to occasional overflow flooding. SubJect to regular overflow flooding. SubJect to severe overflow flooding; permanent cultivation not possible Flood frequency and/or severity precludes any cropping. Slightly SU$ceptible to wind erosion. Moderately susceptible to wind erosion. Severely susceptible to wind erosion. Potential for wmd erosion too severe to allow cropping.

g2 g3 g4 g5 w2 w3 w4 ws

e2 e3 e4 e6

e7 es !2 !3 !4 fS

a2 a3 a4 a6--8

Overland Flow for

IV-i

APPENDIX IV

Determin�tion of Rain fa I I IntensltY for Use the Rational Formula (b�sed on Craw's Nest �alnfal I natal

TABLE 1 Time of Concentration for a Range of Conditions

Diversion Bank - Waterway - Contour Bank

GraEdand CuC'civa'tion Te for ve!oci -ties (m./sea) o.f

Land Slope

(?•J

8-IS

15-.W

H n >6

l8

'"

> 30 10

" "

wo 200 10

300 12

400 13

Land Slope

(%) '"""

Spacing

,,

,, (min)

H "

" lOO '"

000

'"

>00

<00

'"

800

600

100

wo 000

1000

1250

1500

1750

2000

2500

3000

3500

4000

4500

5000

" (min}

Length of Flow

" (min)

Tc Time of Concentration

Rainfall Intensity

Standard Spacing

ds Double Standard Spacing

"

60

lOO 125

'" m <CO l80

>00

;so 000

880

"0

'" ;oo 800

900

1000

llOO 1200

1300

1400

1500

0.55 0 ·' d ·' LO

lO " n

TABLE 2 Rainfall Intensity for the Time of Concentration

)0 (min)

Rainfall Intensi ties 1: 10 Return Period

) mm/hr

no

lo (min)

8l " " 88 88

06

47/48

49/50

51/52

53/54

55/56

8l 58/59

60/61

62/63

64/66

67/68

69/71

72/73

74/76

77/73

79/81

32/84

85/87

38/91

92/94

95/97

" '"' no m

) nnn/hr

Land S l ope

( %)

2

5

10

V-i

APPE ND I X V

Peak R unoff from the I nt erb ank Area for a

Runoff Coeffic ient of 0.5 for the 1 in 10

Desi�n Frequen c y

Bank Channel Drai nage Peak R unoff (c umec s)

S pac i ng Ve l oc i ty De sign m/ sec Rating

ss 0.45 7 . 0

8.5

0.60 7.0

ds 0.45 7.0

8.5

0 . 60 7.0

ss 0.45 7.0

8.5

0.60 7.0

ds 0.45 7 . 0

8.5

0.60 7 . 0

ss 0 . 45 7.0

8 . 5

0.60 7.0

ss standard spacing

200m

0.2

0.2

0.2

0.4

0.4

0.4

0.1

0 . 1

0.1

0.2

0.2

0.2

0.1

0.1

0.1

ds = double standard spacing

f or Bank Le ngths of 400m 600m 800m

0.3 0 . 4 0.5

0.4 0.5 0.6

0.3 0.4 0.5

0.6 0.8 1.0

0 . 7 0.9 1 . 1

0.6 0 . 8 1.0

0.2 0.2 0.3

0.2 0.3 0.3

0.2 0.3 0.3

0.3 0 . 4 0.5

0.4 0.5 0.6

0.4 0.5 0.6

0.2 0 . 2 0.2

0.2 0.2 0.2

0.2 0.2 0.3

1200m

0.6

0.7

0.7

1.2

1.3

1.3

0.3

0.4

0.4

0.6

0.7

0.7

Land

Slope

l%1

10

Bank

Spacing

Standard

Double

Standard

Standard

Double

Standard

Standard

Channel

Gradient

l%1

D.> 0.2

0.1

0.0

0.<

0 · '

0.2

o.o

d 1�1

.20

· " .20

· "

.20

.20

.20

. 20

VI-i

APPENDIX VI

Desi�n Depth of F\ow lor N�rrow Ease Contour Eanks

CFor 1 in 10 desiEn frequencY and a Manninl!'

s n of 0.04)

200 m

' Q {m/sec} {cumec)

.07

"

.02

.01

.4

· ' .4

.1

.1

.1

.1

.1

. 1

.1

.1

d

1�1

.00

.00

.20

.oo

.00

. oo

.00

.30

.00

.00

d Design depth of flow

Channel velocity

Q Peak runoff

Design Depth of Flow for Bank Lengths of

400 m

' Q (m/sec) (cumec)

.00

·" .46

· " .07

.4o

.52

.B

.47

.01

.60

. 7

. 7

. 7

.7

. 2

.7

.7

.4

.4

.4

.<

.7

.2

.7

.00

.00

.on

.35

.30

.00

. 30

.40

.40

.o5

. 35

.00

800 � ' Q

(m/sec) { cumec}

• 33

.42

40

.60

.06

.31

07

5

.o

.3

.0

. 3

.0

. 3

.6

.6

.6

. 0

. 0

.00

.00

00

.00

.45

.40

.oo

1200 m

' Q (m/sec) ( cumec}

.06

.46

.07

. 33

.57

.51

.60

. 30

.o1

.57

.6

.6

.6

.4

.4

.4

.4

• 7

. 7

. 7

Indicates that channel velocity exceeds 0.6 m/sec (maximtun permissible velocity)

Na Not applicable

Peak runoff is calculated from the runoff between the contour banks. Channel velocity is either equal to or exceeds peak flow.

VII-i

APPENDIX VII

Permissible Channel Gradient and Desi�n DePth

of Flow for the Various TYPes of Modified

Contour Banks/Beds for Sma II CroP Areas

Type 1

Contributing Depth of He ight * Bed Area Fl ow ( ha) (m) (m)

1 0.15 0. 25

0.15 0.35

1 - 2 0.20 0.30

0.20 0.40

* Height ; height o f the top of the bed above original ground leve l .

Calculations are based o n a retardance o f E and maximum permissible velocity of 0.5 m/se c . Channel gradients should be greater than 0.5% but wi l l seldom exceed 1%.

Type 2 - for a channel width of 1. 8 m.

Contri buti ng Bed A rea

( ha)

0.5

1.0

2.0

C hannel G radient

%

0.5

1.0

2.0

3.0

0.5

1.0

2.0

0.5

1.0

Depth of Fl ow (m)

0.35

0. 30

0.25

0. 20

0.45

0. 35

0.30

0.55

0.40

Calculations are based on retardance of E and a maximum permissible velocity of 0.8 m/sec . These channel gradients should not be exceeded.

VII-ii

Type 3 - for> a channel width of 1 m.

Contributing Channe 1 De pth of Bed A rea G radient Fl ow

( ha) , (%) (m)

0.5 0.5 0.55

1.0 0.45

2.0 0.35

3.0 0.35

4.0 0.30

5.0 0.30

1.0 0.5 0.65

1.0 0.55

2.0 0.45

3.0 0.40

4.0 0.35

5.0 0.35

2.0 0.5 0.75

1.0 0.60

2.0 0.50

3.0 0.45

4.0 0.40

5.0 0.40

Calculations are based on a retardance C and a maximum permissible velocity o f 1.7 m/sec. By keeping the channel width to 1 m, the land lost to cropping wil l be minimal.

VII-iii

Type 4

Contri buting G radient l�idth (w) De pth of Bed A rea Flow

(ha) ( %) (m) (m)

0 . 5 1 2.0 0.60

2 2.0 0.50

3 2.0 0.40

4 2.0 0 . 35

5 2 . 0 0 . 35

1.0 1 2.0 0.65

2 2.0 0.50

3 2 . 0 0 . 45

4 2.0 0.45

5 2 . 0 0.40

2 . 0 1 2 . 0 0. 70

2 2 . 0 0.55

3 2 . 0 0 . 50

4 2 . 0 0 . 50

5 2.0 0 . 45

Calculations are based on a retardance category of B and a maximum permissible velocity of 1 . 7 m/se c .

V I I I - i

A P PEND I X VIII

Furrow V e l oc it ies* for a Ran�e o f Furrow Grad ients

in Sma I I CroP Row Furrows

Furrow Furrow Ve l oc i ties (m/sec) for Manni ng ' s Gradient

(%) 0 .025 0 .035

0.1 0. 12 0.09

0.2 0.16 0.12

0.3 0. 21 0.15

0.4 0.24 0.17

0.5 0.27 0.19

1.0 0.37 0.27

1.5 0.46 0.32

2.0 0.53 0.38

2.5 0.59 0.43

3.0 0.65 0.46

3.5 0. 71 0.50

4.0 0.75 0 .53

4.5 0.80 0.57

5.0 0. 84 0.60

5.5 0.88 0.63

6.0 0.92 0.65

6.5 0.97 0.68

7 . 0 0.98 0.71

8.0 1.06 0. 76

9.0 1.10 0.80

10.0 1.19 0.85

n of

* Based on a hydraulic radius of 0.29 m as measured in the field .

This table assumes that the furrows run at full capacity. Furrows with a steep gradient and a small contributing catchment, such as immediately below a contour bank, may not reach ful l capacity in a 1 in 10 event .

I X-i

A P PEND I X I X

D e s i�n D e p th o f F l o w and C h � nn el C a P a c i t Y f o r

Di v e r s i o n Banks w i t h a Bo t t om W idth o f 3 m

< fo r R e t a rd a n c e C a t e � o r i e s C and D

Retardance Category

c

D

a nd G r adie n t s o f 0 . 4 � n d o . 5% l

Gradient (%)

0 . 4

0 . 5

0.4

0.5

Depth of Fl ow (m)

0.4

0.5

0.6

0.4

0.5

0.6

0.4

0.5

0.6

0.4

0.5

0.6

Vel ocity (m/sec)

0.3

0.5

0.7

0 .4

0.7

0.9

0.4

0.7

1.0

0. 7

0.9

1.1

* Calculations are based on a tra�zoidal cross section.

Channel Capac i ty ( cumec)

0.6

1 .4

2.5

0 . 8

2.0

3.2

1.2

2.0

3.6

1.4

2.4

4.0

Waterway Capacity ( cumec)

D . 6

0 . 0

u

2 . 6

u 3.4

u 4 . 5

s . ' 5 . 6

u 6 . 8

7 . 4

7 . 9

8 . 5

, . ,

1 0 . 2

l l . O

1 1 . 9

1 2 . 7

1 4 . 2

1 5 . 6

1 7 . 0

18.4

19 . 8

2 1 . 3

2 2 . 6

24

25 . 5

2 6 . 9

2 8 . 3

X-i

APPENDIX

B a t tam Width and D e s i2n D e P t � of F l ew fer Wa t e rwaYs with a Bottom W i d t h Less Than 30 m for G r a i n a n d Grazine A r e a s

( f o r 1 l n 1 0 d e s i.en f re Q u e n c y , v e l o c i t Y o f 1 . 2 m / s e c , v e e: e t a l r e ta r danc e C a n d b a n k b a t t e r s o f 1 i n 3 )

3 . '

3 . '

u 4 . 6

6 . I 6 . 1

6 . 1

7. 6

9. I 10

1 2 . 2

1 3 . 7

15

16

15

2 1

2 2 . 9

2 7 . 4

27.4

30.5

3 3 . 5

36.6

3 9 . 6

4 2 . 7

4 5 . 7

48.8

5 1

5 2

59

6 1 . 9

6 7 . 1

o•

o . 3

0 . 3

0 . 3

0.4

0 . 4

0 . 4

0 . 4

0 . 4

0 . 4

0 . 4

3 . ,

3 . '

u

u

4 . 6

4 . 6

6 .

u u , . ,

0 . 4 10. 7

0 . 4 1 2 . 2

0 . 4 15

0 . 4 1 8 . 3

0 . 4 19 . 8

0 . 4 2 1 . 4

0 . 4 2 2 . 9

0 . 4 2 5 . 9

0 , 4 2 7 . 4

0 . 4 30.5

0 . 4 3 5 . 1

0 . 4 3 8 . 1

0 . 4 41 . 2

0 . 4 44.2

0.4 44.8

0.4 54.9

0.4 59.4

0 . 4 64.0

0 . 4 70

0 . 4 7 4 . 7

0 . 4 7 9 . 3

0 . 4 83.9

0 . 4 88.4

0 . 4 9 3 . 0

0 . 4 97.6

0. 3

0 . 3

o . 3

0. 3

0. 3

0 . 0

0 . 3

0 . 3

0 . 3

0 . 3

0 . 3

* B = Bottom "'idth;

Bottom Width <1nd Design Depth of Flo1v for Land Slopes (%) of

3 . '

u

u

4 . 6

, . ,

1 0 . 7

"

1 3 . 7

16

18

2 1

2 2 . 9

2 5 . 9

29.0

30.5

D

0 . 2

0 . 2

0 . 2

0 . 2

0 . 2

0. 2

0 . 2

0 0 . 2

u 0 . 2

0 . 2

2 . 6

1 0 . 7

12.2

15.3

16.8

19.8

2 1 . 4

24.4

28.9

30.5

4

0 . 2

0 . 2

0 . 2

0 . 2

0 . 2

0 . 2

0. 2

a . 2

D = Design depth of flow.

4 . 6

4 . 6

6 . 1

' '

10

"

1 3 . 7

I S 18.3

2 1 . 4

24.4

2 2

3 0 . 5

0 . 2

0 . 2

0 . 2

0 . 2

0 . 2

0 . 2

0 . 2

4 . 6

4 . 6

6 '

0 · ' 12

1 3 . 7

1 5 . 2

18

2 1 . 3 24.4

2 7 . 5

30.5

0 .

0 . 2

0 . 2

0 2

0.2 0 . 2

0 . 2

0 . 2

4 . 6

u

, . ,

"

13

15 . 2

1 8 . 3

2 1 . 3

2 4 . 4

22

30.5

0 . 2

0 . 2

0 . 2

4 . 6

u

6 . I 2 . 6

, . ,

1 0 . 7

12

1 3 . 7

1 5 . 2

1 9 . 8

22.9 27.4

30 .5

8

0 . I 0 . 2

0 . 2

0 . 2

0 . 2

0 . 2

0 . 2

9 . I 1 0

1 2

13

IS "

2 2 . 9

27.4

.30.5

10

0 .

0 . 1

0 . I 0 . I

X I - i

A P PE ND I X X I

B o tt o m W i d t h a n d D e s ie:n De Pth o f F l o w f o r

W a t e rw a Y s �l i t h a B o tt o m W i d t h G r e at e r

Th an 30 m f o r G r a in and G r a z ine: A r e a s

< fo r 1 in 1-c d e s ie:n f r ,e·q u e n c Y , v e e: e ta l

r e ta rdanc e c and b ank b a t t e r s o f 1 in 3 )

Land Waterway Bottom Depth of Vel ocity Sl ope Capaci ty Wi dth Fl ow (m/sec)

(%) ( cum ec) (m) ( m)

0 . 5 28.3 43 . 2 0.52 1.2 26.9 41.1 0.52 1.2 25 . 8 38 . 7 0.52 1.2 24.1 36 . 5 0.52 1 . 2 22.6 34.4 0.52 1. 2 2 1. 2 32.3 0.52 1 . 2 19.8 29.8 0.52 1 . 2

1.0 28.3 67. 1 0.37 1. 1 26.9 61 . 8 0.37 1.2 25.8 59.4 0.37 1.2 24. 1 56 . 9 0 . 37 1.2 22 .6 51 . 8 0 . 37 1. 1

2 1 . 2 48.7 0.37 1 . 2 19. 8 45.7 0.37 1.2 1 8 . 3 42.6 0.37 1 . 2 16.9 39.6 0.37 1.2 15.5 36.6 0.37 1. 1 14.2 33.5 0.37 1 . 1

1 . 5 28.3 88.4 0.27 1 . 2 26.9 83.8 0.27 1. 2 25 . 8 79 . 2 0.27 1 . 2

24.1 76.2 0.27 1.2 22.6 71.6 0 . 27 1.2

21.2 67.1 0.27 1. 2

19 . 8 6 2 . 4 0 . 27 1.2

18.3 57.9 0.27 1 . 2

16.9 53.3 0.27 1.2

15.5 48.7 0.27 1. 2

14 . 2 44. 1 0.27 1.2

12.7 41.1 0.27 1.2

11.3 36 . 6 0.27 1.1

9 . 9 32 0.27 1.1

2.0 28 . 3 9 7 . 5 0 . 24 1.2

26.9 93.0 0.26 1.2

25.8 88.4 0.24 1 . 2

24.1 83.8 0 . 24 1.2

22.6 79 . 2 0.24 1.2

2 1 . 2 74.7 0 . 24 1 . 2 19.8 70 . 1 0.24 1 . 2

' 18.3 64.0 0 . 24 1. 2

16 . 9 59 . 4 0 . 24 1 . 2

15 . 5 5 4 . 9 0 . 2 4 1 . 2

14 . 2 4 l L 7 0 , 24 L 2 12.7 44. 1 0.24 1. 2 •

1 1.3 39.6 0 . 24 1 . 2 9.9 35 . 1 0 .24 1.2

X I I - i

APPE NDIX XI I

Desi�n DeP th of Flow fo r W a t erwaYs *

For Smal l C roP A reas

Catchment Land Table Drain Trapezoi dal Waterways , W ith S idesl ope Batters

Area

( ha )

1

2

4

6

9

*

Waterways Sl ope of 4 i n 1

(%) Wi dth Depth of Bottom Top

(m) Flow Wi dth Wi dth (m) (m) (m)

2 1 . 0 0.50 0 . 3 2 .7

4 1.0 0.40 0 . 3 2 . 3

7 1.0 0 . 30 0 . 3 2 . 1

2 1.2 0 . 50 0 . 3 2 . 9

4 1. 2 0.40 0.3 2.6

7 1 . 2 0 . 35 0 . 3 2 . 1

2 1.2 0 . 60 0.3 3.3

4 1.2 0.50 0 . 4 2 . 8

7 1 . 7 0 . 35 0 . 4 2 .6

2 1 . 4 0 . 60 0.4 3.6

4 1 . 5 0.50 0 . 4 3.2

7 2 . 3 0. 35 0 . 4 2 . 8

2 1.8 0 . 60 0 . 4 4 . 0

4 2.4 0.50 0.4 3 . 6

7 3 . 4 0.35 0.5 3. 1

(i) For 1 in 10 design frequency.

(ii) Maximum permissible velocity of 2.2 m/sec .

Depth of Fl ow (m)

0 . 30

0 . 25

0 . 22

0.33

0.30

0 . 23

0 . 38

0. 30

0 . 27

0 . 40

0. 35

0 . 30

0 . 45

0 .40

0.32

(iii) Retardance B for table drain waterways and retardance C for trapezoidal waterways .

XI I I - i

APPEND I X X I I I

Bot ani c a l Name of t h e Common P l an t S Pe c ies

Listed in t h is P u b l i c a t ion

Common Name

African star grass Angleton grass Buffel grass Columbus grass Creeping blue grass Fescue Green couch Green panic

Indian blue grass Kangaroo grass Kikuyu Love grass Makarikari grass

PaspalUl!l Phalaris

Pitted b lue grass Queensland blue grass Rat ' s tail grass Rhodes grass

Setaria (Kazungula) Wire grass

Lucerne Medics

Siratro White clover

Bo tan i ca 1 Name

PASTURE GRASSES

cynodon nlemfUensis Diahanthium aristatum Cenchrus ciliaris Sorghum almum Bo thriochloa insculpta Festuca arundinacea Cynodbn dactylon Panicum m=imum (var . trichloglume) Bothriochloa pertusa Themeda australis Pennisetum clanrkstinum Eragrostis spp . Paspalum co loratum (var. makarikariense) Paspalum di latatum Phalaris aquatica

Bothriochloa rkcipiens Diehanthium seriaeum Sporobo lus spp . Chloris gayana

Setaria anceps Aris tida spp .

PASTURE LEGUMES

Medieago sativa Medicago seute llata Medieago truncatula (var. truncatula) Maeroptilium atropurpureum Trifo lium repens

WEED AND WOODY WEED SPECIES

Barnyard mil let Blady grass Bracken fern Carpet grass Lantana Turnip Verbena Wattle

Echinoehloa erus-galli Imperata cy lindriea Pteridium spp. Axonopus affinis Lantana eamara Rapistrum rugosum Verbena rigida Acacia spp .

Cul tivars

Bowen

Bambatsi

Sirosa Australian

Pioneer Calli de Kazungula

Snail Jemal ong Cyprus

XIV-i

APPENDIX XIV

P o ten t i al o f M a j o r Pas t ure S Pe cies fo r

the Crow ' s Nes t Dis tri c t

Rhodes grass

Green panic

Paspalum

Kikuyu

Phalaris and Fescue

Kazungula Setaria

Makarikari grass ( cv . Bambatsi)

Columbus grass

Silk prenural forage sorghum

Rhodes grass is well adapted to most soils in the district. I t will t olerate high sodium levels which often occur in the soi l s of the Marburgs LRA. It requires an availab l e soil phosphorus l evel of at least 15 p .p . m . (bicarb onate extraction) . Persistence during drought is poor.

Green panic is suitable for fertile soils (Basalt West and Basalt East LRAs) or on other soils where nitrogen fertilizer is applied to maintain stands .

Paspalum can be used on most soils in the district . Phosphorus requirements are similar to those for Rhodes grass .

Kikuyu is suitable for climatic zones Al and A2 . In zon6 B and C it can be used in areas where extra moisture is available ( such as waterways and creek beds) . Phosphorus requirements are similar to those of Rhodes grass but it needs higher levels of nitrogen .

Phalaris and fescue are suitable temperate grasses for most soils in climatic zones Al and A2 . These grasses are eventually invaded by tropical grasses such as paspalum .

Kazungul a S etaria is suitable for most soils in the wetter sections of climatic zone B .

Bambatsi i s recommended for se lf mulching soils with a coarse surface structure .

Co lumbus grass is a useful pioneer grass, producing quick feed, especially on fall owed soi ls . Other grasses such as Rhodes grass gradually do minate the pasture .

Silk prenural sorghum is nowadays preferred to Sorghum almum.

Indian blue grass

Creeping b lue grass

Angleton grass

Buffel grass

White clover

Medics

Lucerne

Siratro

XIV-ii

Indian blue grass is a low growing and mat forming species whi ch promises to be useful for vegetating waterways . It may also have application as a pasture grass in climatic zones B and C . This grass will grow and persist under conditions o f low fertility but is responsive to improved fertility conditions . It wi ll tolerate heavy grazing .

Creeping blue grass shows promise for pasture sowing in climatic zones B and C . As for Indian blue grass it persists under conditions of low fertility and is tolerant of heavy grazing .

Angleton grass is tolerant o f waterlogging and even submersion for short periods . I t i s most adapted to heavy clay soils and may be better than Bambatsi in many pasture sewings . It is relatively easy to establish and tolerates low soil fertility and heavy grazing.

Buffel grass is more drought tolerant than Rhodes, but generally the summer growing season in the Crow' s Nest District is too short for consistent production from this grass .

White clover is suitable for most soils in climatic zones A and B but requires a re latively high level of avai lable phosphorus (30 p .p .m. ) . White clover wi ll tolerate low pH leve l s , but productivity will decrease .

Medics are wel l adapted to soi ls of the district with a pH of 6.5 or highe r . Medics are therefore not suitable for most soils of the Basaltic Red Soils LRA . In the Granites, Marburgs and Metamorphics LRAs , surface pH varies from 6.0 to 7.5 and soils should be tested for pH before medics are planted .

Lucerne is suitable for wel l drained soils with a high plant available water capacity. It requires a high l evel of avai lable phosphorus (40 p . p . m . ) . It is not suitable for climatic zone Al because of the high rainfall .

Siratro is suitable for soils other than cracking clays in the district . However, the growing season is too short for the best development of Siratro . It does not perform wel l in climatic zone A, because of low summer temperatures . Phosphorous requirements are much lower than for white clover .

XV-i

APPENDIX XV

Re s e a � c h a n d M on i t o �i n � P � o J e c t s in the C ro w'

s N e s t D i s t r i c t ( J a n u a �Y 1982>

Project

1 . Contour ripping and contour cultivation of native pasture.

2 . Fertilizing native pasture .

3. Sod seeding Dolichos lab lab

4. Sod seeding oats.

5. Pondage banks on scalded areas .

6 . Fencing and pl ant·ing kikuyu in scalded areas .

7. Small crop farm layout according to speci fications in section 7 . 5

Date Commenced

1980

1980

1980

1979

1978/ 1979

1978

i 1979

ii 1981

Co-operator

G . Trost

G . Trost

G . Trost

Kahler Ashford

Weis Morice

Gordon

E . Lang

M. Barton

AMU

FMH(TC)MF

FMH(TC)MF

FMH(T(:)MF

Geham I BSd

FMH(TC)MF

FMH(TC)MF

Purrawunda

PurrawW1da

Results

Contour ripping and contour cultivation does not increase pasture yield.

P and K do not increase pasture yield. N does increase pasture yield but the economics of application are questionab l e .

One cultivation plus a sod seed operation and superphosphate are required.

Direct sod seeding is not entirely satisfactory .

This is being undertaken to reduce erosion and promote grass growth .

Some recovery . Kikuyu is spreading slowly. Requires N, P, K .

Layout i s satisfactory . Some soil movement in rows after 80 lTffil of rain in 8 hours in December 1980. Siltation and excessive grass growth in waterways is the major problem.

As above but ·waterway constructed sub surface .

Progress

Complete.

Complete .

Complete .

In progress .

Long term monitoring.




Land Management Field Manual - Crow's Nest · This manual identifies (Map 3) and describes the land resource areas for the Crew's Nest district, and collates all available information

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