Nutrient Transport of Fertilizers from Turfed Landscapes

Marty Petrovic Professor of Turfgrass Science Dept. of Horticulture Cornell University

What will be covered Transport Processes Water flow Soluble nutrients Sources Turfs Role in Nutrient Transport Water flow Nutrient fate Landscape types Management Factors Affecting Transport

What will be covered Management Factors Affecting Transport Maintaining plant density Fertilization practices Sources Rates Timing Other management options Grass selection Irrigation Clippings Research Questions

Water flow-nutrient movement

Impacts to and surface water quality from:

• Atmospheric Deposition

• Wastewater (sewage disposal systems)

• Fertilizer

Fertilizer

bb

runoff

leaching

ET

Inputs of Nutrients in a Turfgrass System

Inputs: Fertilizer Plant debris (tree leaves, etc)

Compost Rainfall Irrigation water Dust Pollen Pet waste Wildlife

What will be covered Transport Processes Water flow Soluble nutrients Sources Turfs Role in Nutrient Transport Water flow Nutrient fate Landscape types Management Factors Affecting Transport

Pathways of Nitrogen Movement in a Turfgrass System

Soil Organic Nitrogen (SON)

Fertilizer ApplicationBNF

ClippingsN2O Denitrification

Runoff

NO3

Leachate

Plant Uptake NO3 / NH4

Mineralization R- NH2→ NH4→ NO3

&Nitrification to NO3

Volatilization

Immobilizatiizationto R—NH2

Immobilizatiizationto R—NH2

NO3

Leachate

Surface water

Pathways of Phosphorus Movement in a Turfgrass System

Source: Mississippi State Extension

Landscape type and runoff volume

0

50

100

150

200

250

300

350

400

High Maint. Turf Wooded Low Maint. Turf

Ru

no

ff (

mm

)

Winter

Fall

Summer

Spring

Easton & Petrovic, 2008, 2 yr amount during wet years

On sites with moderate to low potential for runoff, high maintenance lawns had

about half the amount of total P runoff compared to unfertilized low maintenance lawns and wooded sites

On sites with high potential for runoff, high maintenance lawns had: * about 3 times the amount of dissolved P * ¼ the amount of particulate P *the same amount of total P in runoff compared to unfertilized low maintenance lawns and wooded sites

Suburbanization: *increased the average concentration of P in a perennial stream *reduced the N concentration

Lawn types and nutrient fate

• 5 inches wide x 4 ft long channel gutter at the bottom of 4 ft x 20 ft plots

• Drains into tipping buckets

– Recorded with event logger

• Subsamples collected &

bulked monthly

Treatments (8 lawn types) – Kentucky bluegrass sod+ pesticides, fertilizer, and

irrigation – Turfgrass + pesticides, and fertilizer – Turfgrass + fertilizer – Turfgrass (only mowed)

• 3 lbs N 1000 sq.ft.-1 yr-1 • 0.3 lbs P2O5 1000 sq.ft.-1 yr-1

• 2,4-D, MCPP, Bifenthrin, and Pendimethalin • 4 applications yr-1

– Crabgrass – Turfgrass + Crabgrass (1:1) – Broadleaf weedy lawn(dandelion, plantain, clover) – Turfgrass + Broadleaf weeds (1:1)

• Turfgrass, Broadleaf, and Mixture plots established from sod • Crabgrass plots established from seed and reseeded annually

Leachate volume by lawn type

Treatment

Bro

ad+

Turf

Bro

adle

af

Cra

b+

Tu

rf

Cra

bg

rass

Turf

Turf

+F

Turf

+P

+F

Turf

+P

+F

+I

Tota

l le

acha

te (

mm

)

0

100

200

300

400

500

B

ABAB

A A AA

AB

Total Precipitation 1153 mm

Slavens, 2010

Total Runoff by lawn type

Total Runoff

Treatment

Bro

ad

lea

f+tu

rf

Bro

ad

lea

f

Cra

bg

rass+

turf

Cra

bg

rass

Turf

gra

ss

Turf

gra

ss+

F

Tu

rfg

rass+

F+

P

Turf

gra

ss+

F+

P+

I

Runoff V

olu

me (

mm

)

0

20

40

60

80

100

120

140A

ABC

BC

ABC

ABC

C

C

AB

Total Precipitation 1153 mm

Slavens, 2010

Results from the 1st two years:

• Regardless of type of lawn, lawns with low plant density and wet soils had the highest amount of runoff

• Runoff volumes and nutrient losses were most significant during establishment period and greatly decreased with time

• Phosphorus loss in runoff is primarily a function of runoff volume, more water running off more phosphorus runoff

Results continued

• If you don’t fertilizer a Kentucky blue grass lawn, in 2 yrs it has runoff problems!

• If not overly irrigated, a lawn fertilized and maintained according to a typical four step program, posses no greater risk water quality (nutrients) from being fertilized compared to other lawn types.

Sink for Nitrogen in a Turfgrass Soils

(1.7 lbs N/1000 sq.ft/yr)

(top 3.3 ft of soil)

Steve M. Raciti, Ph.D. Thesis 2010, Cornell Univ., Baltimore Long Term Urban Ecosystem Study

Mass Balance Nitrogen in Residential Soils

Steve M. Raciti, Ph.D. Thesis 2010, Cornell Univ., Baltimore Long Term Urban Ecosystem Study

Nitrogen Mass Balance

Residential Forest Source

N Inputs

Atmospheric Dep (lbs

N/acre/yr) 9.7 9.7 Groffman et al. 2004

Fertilizer (lbs N/acre/yr) 72.7 N/A Law et al. 2004

N Losses

Leaching (lbs N/acre/yr) 12.3 3.8 Groffman et al. 2009

(4 yr average)

N Sequestration

N accumulation in SOM (lbs

N/acre/yr)

72.4 N/A Residential sites with

agricultural land-use

history.

What will be covered Management Factors Affecting Transport Maintaining plant density Fertilization practices Sources Rates Timing Other management options Grass selection Irrigation Clippings Research Questions

Turfgrass Density and Runoff:

Double the amount of turf shoots in a lawn (32 to 64/sq.inch) and

reduce the amount of runoff by 2/3

(Easton, Z.M., and A.M. Petrovic. 2004. Fertilizer source effect on ground

and surface water quality in drainage from turfgrass. J Environ Qual 33: 645-656.)

Fertilization:

Sources

Rates (limited information)

Timing (others)

Nitrogen Source Impact Percent of applied nitrogen that leached as a function of nitrogen source (4 lbs N/1000 sq ft/yr). Source Year1 Year 2 Year3 mean -----------------------------------------% ------------------------------------------- ureaformaldehyde 4.0 ab* 4.2 2.9 b 3.7 b methylene urea 1.7 ab 4.6 6.7 b 4.6 b IBDU 1.9 ab 6.9 4.1 b 4.9 b SC- urea-non wax 4.9 ab 4.8 4.8 b 4.8 b SC urea-wax 1.7 ab 7.4 5.8 b 5.4 b urea 1.6 b 4.1 12.1 b 6.1 b

calcium nitrate 0.9 b 5.0 29.7 a 12.5 a PC-urea (100day) 2.4 ab 6.4 4.1 b 4.2 b PC-urea (200day) 0.5 c 3.1 2.5 b 2.0 b biosolid 5.6 a 3.9 2.2 b 3.7 b NS** Rainfall (mm) 747 1213 1512 * Means within columns followed by different letter are significant (P<0.05), Tukey’s studentized

test. ** NS=no significant differences (P<0.05). Petrovic, 2003.

Sources of P Kussow, 2008

Fertilizer Amount

Source Runoff P

in/yr lbs/acre/yr

None 1.6 0.62

Synthetic 1.1 0.27

Organic 0.7 0.24

LSD 0.2 0.12

Irrigation Impact Nitrogen Irrigation Amount amount NO3-N Conc. lbs N/1000

sq.ft./yr in/wk mg/L 2 0.5+ 0.9 1.5 1.8* 5 0.5 1.2 1.5 4.0* unfertilized 0.5 0.5 1.5 0.4 + ET amount * Significantly higher than unfertilized control. Morton et. al.

(1988) on Poa pratensis, Festuca rubra, urea + FLUF

Summary of risk

Fertilizing at establishment

Late fall applications

Over irrigation

Thin stands of plants

Site factors (soils, hydrology,etc)

Others

Research Needs

Low input grasses

Rates (turf response vs water quality)

Late fall (timing, rates vs water quality)

Determining when to fertilizer (N)