Water slides

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Water Management and Irrigation

Water Management and Irrigation

• Turf 75-85% of plant is composed of water.

• Turf in northeast 1-2” water/week.

• Some functions of water in the plant:

• transport solvents and nutrients

• Involved with P.S.

• Involved in gas exchange

• Cooling the plant

• Soil is the reservoir for holding water for plant use.

• Soil/plant factors that effect water availability for the plant:

a) soil texture - course soils hold less available water

b) Root depth- plant with a 6"root system has half the water available for uptake as a plant with a 12" root system

d) Infiltration Rates

d) Percolation rates

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Transpiration = water loss from plant

Function - gas exchange

- cools plant

- moves plant nutrients, amino acids etc.

Evaporation = water loss from soil. Effected by:

•turf density

•water content

•soil type

Turfgrass Water Use Rates:

Evapotranspiration = (evaporation + transpiration)

California Department of Water resources

Water use rates effected by a) Turf species b) Light-solar radiation and night c) Fertility N/K d) Mowing heights e) Soil types f) Temperature g) atmospheric conditions:

• relative humidity • atmospheric moisture-fog • rain-precipitation • condensation in form of dew • vapor content of

turf canopy • wind

Water use rates can be reduced with chemicals:

PGR’s and Anti-transpirants

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WATER REPLENISHMENT INTO THE ROOT ZONEI ) Precipitation - two major factors:

1) duration2) intensity

- Infiltration Rates

- Percolation rates

1) Need good clean source ( quality)2) Need a good amount (quantity)3) Need a dependable and properly

designed irrigation system

2) Irrigation:

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IRRIGATION SYSTEMS

Evolution of Turfgrass Irrigation Systems

snap valves- hard to find at night, labor intensive, over or under watering

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Computerized systems

Controlled home, office, or field

Turfgrass BMP’s for

Water Quality and Quantity

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Best Management Practices for Water

• Goals

• Promote water conservation

• Preserve and improve water quality

What are Turfgrass BMP’s for water management?

Water Quality

• Best Management Practices for Turfgrass water

• Pesticide

• Fertilizer

Water Quantity or Distribution Management

a) Irrigation system features and technologies that aid in water

conservation

b) Management Practices that aid in water conservation

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Water Quality

• Best Turfgrass Management Practices for water quality.

Practice IPM

Controlling Turfgrass Pests second edition By:Fermanian, Shurtleff, Randell, Wilkinson, Nixon

• Avoid applying fertilizers and pesticides on hard surfaces such as cart paths and road ways• Avoid applying pesticides or fertilizers close to waterways (Establish Buffer Zones)

AVOID HIGH RATES OF SOLUBLE NITROGEN ON A

FREQUENT BASIS OR BEFORE HEAVY RAINFALL

EVENTS

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Water QuantityA) System conservation features conserve water at the source

Isolation valves to isolate and repair leaks

Water Conservation Features that can be retrofitted to both new and older systems:

Install water meters at point of entry to system

Pr = 96.25 x GPMHS x RS*

* Pr = precipitation rateHS = Head spacing RS = Row Spacing

or

Pr = 34650 x gpmº arc x HS x RS

Be aware of sprinkler precipitation rates

Photo USGA Green Section Record Sept./Oct 2000

Check nozzle wear and output

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Use part circles to avoid watering non turf areas

Utilize correct nozzle sizes

Rain Out Switches

Low trajectory nozzles - reduce evaporation or water loss in wind

Low Volume Nozzles

V.S.

High Volume Nozzles

Less Loss Due To:

• Evaporation

• Wind or Drift

• Runoff

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Computerized systems

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Computerized systems allow for:

Greater efficiency

• Run times

• Flow management optimizes programs

• Cycle and soak options

• Irrigation adjustments (water budgeting) from one location

From Office or Home

From Field

Remote off site• Shut down capabilities

• Water adjustment capabilities

Automatic Shut Down

• Rain events

• Electrical Storms

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Monitor weather

Evopotranspiration Rates

Temperature

Humidity

Wind

Turfgrass water use in the Northeast

Tools Available:

Radio

Internet

Television

Rain gages

Evaporation pans

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weather satellites

Irrigation decisions and Management Practices that aid in water conservation

• “Hard to decide when to irrigate”• Apply the optimum amount without over or under watering!

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a) diseaseb) shortened root systemsc) compactiond) algaee) thin or week turff) in general poor plant health

Overwatering can lead to:

P.M. A.M.

rough>fairway>tee>green

• Compacted soils often require lighter and more frequent applications

IRRIGATION TO REPLENISH SOIL WATER

• CT 1-1.5” water per week• If possible “water to replenish” in early morning

Possible sequence -

>Turfgrass species

>Turfgrass use

> Micro-climates/environments

> Slope

> Compaction

> Forecasts

> Cultural practices

Determining irrigation needs (scheduling):Determining irrigation needs:

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>Light intensity

>Precipitation rates of sprinklers

>Nozzle size

>Soil moisture levels using> tensiometers >soil probes

>Soil type

Determining irrigation needs:

Utilize the correct sprinkler head and precipitation rates for soil type and slope

Determining irrigation needs:

2) Check indicator areas

1) Probe soils daily-check moisture content (moisture tensionmeters available)

Determining irrigation needs:

3) Use of wetting agents localized dry spots

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5)Keep an eye on weather-humid weather cut back-syringe if needed.

6)Hold off on irrigating as long as possible-however, soil hard to re-wet once it dries out

4)Water as close to daylight as possible

-this reduces time of leaf wetness -reduces over watering if sprinkler sticks

Determining irrigation needs:

Wilt Signs• Loss of turgidity• Turns blue in color• Foot printing

WATER MANAGEMENT:WILT / HEAT / DROUGHT *

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Heat stress

Two types:

1. IndirectIn general when air and soil temperatures exceed 86ºF for extended periods• result reduction in root and shoot

growth• increase in respiration and reduction

carbohydrate production

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Damage from golf carts driving on water stress (wilted) turf

Photos USGA Green Section Record

2. Direct• Occurs with rapid increase in

temperature i.e. 104º F for short time

• Most common type of direct is scald

•Scald (Direct Heat Stress)Hot sunny daysRapid heat build up >104 ºFStanding water or in some cases

in extremely saturated thatchRapid loss of oxygen Death within hours

Turf may be killed by combination of:• excessively wet soils• high day and nighttime temperatures• mechanical injury from mowers when mowing

under wet conditions

Scald on bentgrass tee photo: Peter H. Dernoeden PH.D USGA Green Section Article March April 2006

Understanding Wet Wilt by Peter H. Dernoeden PH.D

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Wet Wilt•Bridges Direct and Indirect•Transpiration loss greater than uptake but water is in soil. •Occurs when limited root system.

Conditions favoring wet wilt:•Water on surface or in thatch absorbs heat from sun•Soil temperatures in putting greens on hot sunny days may be hotter than air temp.•Water logged soils

•High temp and humidity with extended precipitation

Annual bluegrass putting green damaged by spiking in the heat of the day during a wet wilt event Photo: Peter H. Dernoeden PH.D

USGA Green Section, March April 2006 , Understanding Wet Wilt

Syringe for wilt:Dry wilt•Transpiration greater than water uptake by roots•Hot, dry, windy, bright days

Wet Wilt•Transpiration loss greater than uptake

•Saturated or waterlogged conditions

•Limited root system.

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Syringing - light application of water to cool off plant and slow transpiration rates. No wetting or soil water replenishment.

Syringing to alleviate wilt

TGIF- The necessity of hand watering greens

http://www.youtube.com/watch?v=kw9ufwNLr7Q

Aerate to relieve compaction and increase water infiltration to the rootzone

Irrigate in early morning to reduce water loss due to evaporation and wind

Raise mowing heights > increased root growth > increase water availability

Utilize a well balanced fertilizer plan for the turf species being grown

Designate naturalized areas for lower maintenance and water use

Management Practices to reduce water input under dry conditions and water conservation

Rackliffe and Troll (1982)

Management Practices continued:

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Utilize wetting agents to improve water infiltration

Through Irrigation systems

Sprayer

or

granular

Hose

Management Practices continued:

Wetting AgentsSurfactants = chemicals that cause a physical change at the surface of liquids.

Thus SURFice ACTive AgeNTS

Surfactants include- wetting agents, spreaders, stickers, emulsifiers, detergents, dispersants etc.

Management Practices continued:

In Turf

• Most wetting agents - Non Ionic- (No Charge-thus they will not react with other ions in the soil)

• All contain a water-soluble hyrophilic group attached to a oil-soluble (lipophilic group)

Characteristics and Terminology

Wetting agent molecule Water soluble

group (polar) hydrophilic

OIL-Soluble Hydocarbon group (non polar) hydrophobic

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H+ H+

O-

•Polarity- i.e. water is dipolar (both negative and positive ends)

•Water will not bond with non polar molecules- in fact water would be repelled by non polar substances

•Most organic matter is non-polar

• Non Polar portion of the wetting Agent will bond with non polar portion organic matter

• Polar portion of wetting agent will bond with water

Sand particle

Water-repellent organic coating with non polar ends that repel water

Wetting Agent polar end attracts water (hydrophilic)

H HO

H HO

H HO

H HO

H HO

H HO

H HO

•600 Golf Course Superintendents

• 87% use wetting agents as part of regular maintenance program

• 11% use them in “certain situations”

Four primary purposes:

• 42% relieve localized dry spot

• 32% to aid in water management

• 11% improve soil drainage particularly on non-water repellent soils

• 9% improve pesticide and fertilizer performanceSource Golf Course Mgt. June 2004, Keith Karnok Ph.D. University of GA

Survey

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Other uses:

• Relieve surface tension of water

• Remove morning dew

• Suppress poa annua seed head (early 90’s)

• Reduce run-off

• Summer stress reduction

• Water usage reduced

Water drop without wetting agent

Water drop with wetting agent applied

Low contact angle

High contact angle

• Numerous Wetting Agents

• All vary significantly

• Different label rates

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