TILLAGE EFFECTS ON SOIL PROPERTIES Dick Wolkowski Department of Soil Science University of Wisconsin
TILLAGE EFFECTS ON SOIL
PROPERTIES
Dick Wolkowski
Department of Soil Science
University of Wisconsin
WHAT IS TILLAGE
THE PHYSICAL MANIPULATION OF
THE SOIL FOR THE PURPOSES OF:
Management of previous crop residues
Control of competing vegetation
Incorporation of amendments
Preparation of a seedbed
SOIL PROPERTIES AFFECTED
BY TILLAGE
Crop residue cover
Soil test measurements
Nutrient availability
Structure and aggregate stability
Water relationships
Temperature
Strength
SURFACE CROP RESIDUE
INTERACTS WITH OTHER FACTORS
Impact on erosion
Cooler soils
Conserves moisture
Affects soil physical
properties
Affects carbon and
nutrient cycling
TILLAGE EFFECT
EROSION ON CLEAN-TILLED
GROUND, DANE CO., WIS.
CROP MANAGEMENT EFFECT
EROSION ON CORN SILAGE
GROUND SHAWANO CO., WIS.
TILLAGE INTENSITY IN WISCONSIN
VARIES BY CROP
0
10
20
30
40
50
60
70
Corn Soybean Forage
% o
f Acr
eage
NT
MT
RT
CT
CTIC, 2002
EFFECT ON SOIL TEST
Nutrients “stratify” in long-term no-till
Surface acidification
Soil sampling concerns
Benefit to P and K banding
Banded fertilizer response more likely in
no-till
SOIL TEST STRATIFICATION FOLLOWING
FIVE YEARS OF TILLAGE MANAGEMENT,
ARLINGTON, WIS.
0 10 20 30 40 50 60 70
NT
CH
SOIL TEST P (ppm)
0 25 50 75 100 125 150 175 200
NT
CH
SOIL TEST K (ppm)
6-8" 4-6" 2-4" 0-2"
5 5.5 6 6.5 7
NT
CH
SOIL pH
Wolkowski, 2003 (Corn/soybean rotation)
REDUCED TILLAGE IS MORE
RESPONSIVE TO BANDING
Positional availability
Surface vs. sub-surface
Wheel track vs. non-wheel track effects on
root distribution
Reduced P and K fixation by the soil
Reduced K uptake from zones of poor
aeration
FERTILIZER PLACEMENT AFFECTS
CORN ROOT DISTRIBUTION (0-15 IN.)
Root length (km/m3)
Tillage Fert.
placement
Row Untracked
Inter-row
Tracked
Inter-row
CH ROW 17.1 3.0 0.8
CH INTER-ROW 12.0 4.4 1.4
NT ROW 19.8 2.5 0.8
NT INTER-ROW 10.8 6.1 1.5
Kaspar et al., 1991
CC SbC
CH ST NT CH ST NT
------- % ------- ------- % -------
NONE 2.23 2.37 2.35 1.65 1.34 1.40
BDCT 2.35 2.19 2.51 2.51 2.18 1.40
2 x 2 2.85 3.26 2.31 2.46 2.58 2.16
EFFECT OF ROTATION, TILLAGE, AND FERTILIZER ON
CORN K CONCENTRATION 45 DAP, ARLINGTON, WIS.
Wolkowski, 2003
CORN RESPONSE TO STARTER:
PLANTING DATE AND TILLAGE
0
5
10
15
20
25
YIE
LD
RE
SP
ON
SE
(b
u/a
)
PLOW NO-TILL
EARLY MAY
LATE MAY
BUNDY AND WIDEN, 1991 (3 YR. AVG.)
LOWER N AVAILABILITY IN
REDUCED TILLAGE SYSTEMS
No-till/reduced tillage:
Lower and slower mineralization
Greater immobilization
Volatilization of ammonia from surface urea
and urea-containing materials
Potential for increased denitrification
Higher supplemental N rate for >50% corn
residue recommended (30 lb N/a)
CONTINUOUS NO-TILL CORN
TYPICALLY HAS LOWER N UPTAKE
Oshkosh Janesville
Tillage Earleaf N
%
Grain N
%
Yield
bu/a
Earleaf N
%
Grain N
%
Yield
bu/a
MB 2.92 1.57 159 3.10 1.52 145
CH 2.84 1.55 145 3.05 1.50 137
NT 2.76 1.55 146 2.98 1.47 126
Bundy et al., 1992 (3 yr. avg.)
SOIL C AND N DISTRIBUTION AFTER 12
YEARS OF CONTINUOUS CORN
0
5
10
15
20
25
30
35
40
12.5 50 100 200 275 375 525
Depth (mm)
MB
NT
0
0.5
1
1.5
2
2.5
3
3.5
12.5 50 100 200 275 375 525
Depth (mm)
Tot
al N (mg/c
m3)
MB
NT
Karlen et al., 1994
Total C
0
5
10
15
20
25
12.5 50 100 200 275 375 525
Depth (mm)
NO3-N
(ug/
cm3)
MB
NT
NO3-N
Total N
TILLAGE AND DENITRIFICATION
0
0.5
1
1.5
2
2.5
1 2 3 4 5
Sampling time
N los
s (lb/a
/day)
WT N-WT
Tillage affected loss:
MB = 10 lb/yr
CH = 14 lb/yr
NT = 22 lb/yr
No-till
Lower air-filled porosity
Higher microbial
denitrifier population
More surface organic
carbon
Hilton et al., 1994 (all received 100 lb N/a)
TEN BOTTOM MOLDBOARD PLOW
SET AT 11”, WOOD CO., WIS.
TILLAGE HAS A PROFOUND
EFFECT ON THE SOIL PHYSICAL
CONDITION
EFFECTS OF LONG-TERM TILLAGE ON THE
PLOW LAYER PORE SIZE DISTRIBUTION
0
0.02
0.04
0.06
0.08
0.1
0.12
>150 150-15 15-1.5 1.5-0.3 0.3-0.1
Pore Size
MB
NT
Hill et al., 1985
Pore
vol
ume (
cm3/c
m3)
EFFECTS OF TILLAGE MANAGEMENT ON
MACRO-PORE (>0.4 mm) CONTINUITY
0
200
400
600
800
1000
1200
NT MB
Upper Ap
Lower Ap
Upper B
Lower B
Lancaster, Wis.; continuous corn (Logsdon et al., 1990)
Pore
num
ber
(m2)
AGGREGATE STABILITY
INFLUENCED BY
Organic matter and organisms
Texture
Rotation
Tillage
IMPORTANT FOR:
Aeration
Water relations
Productivity
“HEALTHY” CORN ROOT MASS
TILLAGE EFFECTS ON SOIL (0-2 IN.)
PROPERTIES AT LANCASTER, WIS.
TILLAGE STAB.
AGGR.
TOTAL
C
EARTH
WORMS
RUNOFF
% g/kg No./m2 Mg/ha
No-till 46 24 78 2.1
Chisel 34 16 52 --
Plow 36 11 53 0.5
Karlen et al., 1994
WATER-STABLE AGGREGATE SIZE IN THE
0-3 IN. DEPTH AS AFFECTED BY ROTATION
AND TILLAGE
0
0.5
1
1.5
2
2.5
3
CC CSb SbC SbSb
SIZ
E (
mm
)
FALL MB
FALL CH
NO-TILL
Kladivko et al, 1986
EFFECT OF TILLAGE ON CRUST
STRENGTH AFTER A HEAVY RAINFALL
0
0.2
0.4
0.6
0.8
1
1.2
1.4
1.6
1.8
2
8 12 16
ST
RE
NG
TH
(M
Pa)
MB
NT
UNGER, 1984 DAYS
TILLAGE EFFECTS ON SOIL
WATER RELATIONSHIPS
No-till soils tend to have lower porosity and
higher water content
Considerable variability by soil type
Continuous channels in no-till can increase
infiltration rate
TILLAGE EFFECT ON INFILTRATION
0
50
100
150
200
250
300
INF
ILT
RA
TIO
N (
uM
/s)
NT CH
WT
IR
No-till maintains large
pores
Bare soil crusts
Infiltration varies
during season
Wheel traffic
influences infiltration
Ankeny et al., 1990
RELATIONSHIP BETWEEN SOIL MATRIC
POTENTIAL AND VOLUMETRIC WATER CONTENT
0.25
0.3
0.35
0.4
0.45
0.5
0.55
0.6
0 1 2 3.5 5.9 7.4 20 40
WA
TE
R C
ON
TE
NT
(m
3/m
3)
MB
NT
Hill, 1990 MATRIC POTENTIAL (kPa)
TILLAGE EFFECTS ON SOIL
TEMPERATURE
Cooler temperatures associated with
high residue
Residue buffers temperature change
Emergence and early growth affected
No-till systems have been shown to be
5-10% less productive in Wisconsin
SOIL TEMPERATURE AFFECTED BY
TILLAGE AND CROP RESIDUE
0
5
10
15
20
25
30
11-Apr 18-Apr 24-Apr 2-May 9-May 16-May 23-May
DE
GR
EE
C
STRIP-TILL
CHISEL
NO-TILL
2 " DEPTH
MEASURED 4:00-5:00 PM
Effect on in-row soil temperature,Arlington, 1994
0
20
40
60
80
100
Res
idue
(%)
Chisel
Strip-till
No-till
Effect on cropresidue, Arlington, 1994
Wolkowski, 2000
EFFECT OF TILLAGE ON THE EARLY
GROWTH OF CORN, ARLINGTON, WIS.
TILLAGE EMERGENCE V6 V12 SILKING
plt/ft -------- g/plt -------- %
Strip-till 1.6 1.1 28 62
Chisel 1.8 1.1 29 80
No-till 0.7 0.7 18 36
Wolkowski, 2000
STRIP TILLAGE OFFERS
AN ALTERNATIVE TO
FULL-WIDTH TILLAGE
IN-ROW RESIDUE MGT.
ZONE-TILL PLANTER
STRIP TILLAGE OFFERS AN ALTERNATIVE TO
FULL-WIDTH TILLAGE WITH CONSERVATION
AND AGRONOMIC BENEFITS
TILLAGE EFFECTS ON SOIL
STRENGTH
Reduced tillage soils have higher
surface bulk density
Short-term response to occasional
tillage
Traffic management critical
Subsoiling response is likely site
dependent
EFFECT OF PERIODIC PLOWING ON
SOIL BULK DENSITY (0-3 in.)
1
1.1
1.2
1.3
1.4
1.5
1986 1987 1991
g/c
c
CT
NT/PLOW
NT
Pierce et al., 1994
TILLAGE INFLUENCES
RESISTANCE TO PENETRATION
Lower penetration
resistance in NT at depth
compared to chisel and no-
till
Greater penetration
resistance in wheel track
Larney and Kladivko, 1989
SOIL PHYSICAL PROPERTIES AND CORN
YIELD AS AFFECTED BY TRACKED AND
WHEELED VEHICLES
TYPE BULK
DENSITY
HYDR.
COND.
AIR-FILLED
PORE SPACE
YIELD
g/cc uM/sec % Bu/a
Un-
tracked
1.28 26.0 17.8 166
Steel-
tracked
1.38 13.0 9.7 148
Rubber-
tracked
1.46 7.8 7.7 --
Wheel-
tracked
1.50 2.7 4.7 139
Brown et al., 1992
Given enough horsepower man can
do some really dumb things
Compaction affects the soil
- structure
- porosity
- aeration
- strength
Plant growth affected
- root growth
- nutrient uptake
- water utilization
CORN AND SOYBEAN YIELD AS AFFECTED
BY DEEP TILLAGE, MANITOWOC, WIS.
TILLAGE SOYBEAN
1997
CORN
1998
SOYBEAN
1999
CORN
2000
------------------------ bu/a ------------------------
NT 30 213 57 176
VR 40 188 58 172
ZB 51* 226* 59 192*
Wolkowski (unpublished)
NATURAL ALLEVIATION OF COMPACTION
ON A SILTY CLAY LOAM SOIL
-10
0
10
20
30
40
50
60
1988 1990 1991 1992 1993 1994 1995
YIE
LD
RE
DU
CT
ION
(%
)
10 T
20 T
Al-Adawi and Reeder, 1996
SUMMARY Tillage management can greatly modify
soil properties related to soil quality and
crop growth
Tillage intensity will impact residue
management and soil consolidation
Many physical and chemical properties
are affected
High residue systems need “tweaking” in
Wisconsin
Better traffic and tillage management will
enhance soil quality