Manure 101:Nutrient Management and the

Dairy Industry.

Manure 101:Nutrient Management and the

Dairy Industry.

Kevin Erb

UW-Extension NPM Program

Kevin Erb

UW-Extension NPM Program

University of Wisconsin - Extension

UW-Madison College of Agricultural & Life Sciences

University of Wisconsin - Extension

UW-Madison College of Agricultural & Life Sciences

Farmer View of Site-Specific Future Manure Regulations

What is Nutrient Management?Common Sense.

Combine on-farm nutrient sources, with commercial fertilizer, to meet crop need.

On-farm nutrient sources (manure)

Commercial fertilizer

Minimize nutrient losses

Soil reserves

Environmental Aspectsof Manure

Nutrients Nitrogen Phosphorus Potassium

Bacteria/Pathogens

BOD

Nitrogen

Groundwater Concerns EPA Standard: 10 ppm Blue Baby Syndrome

Hypoxia

Hypoxia

Phosphorus

Surface Water Concern

Algae Growth

Environmentalist’s view of how farmersmanage manure.

Phosphorus

Movement Soil attached is most common route

1 lb P = 500 lb algae One ton soil eroded = 1 ton algae in water

Stop Erosion, Solve Big Part of the

Problem National Buffer Initiative (USA)

Potassium

Dairy Animal Health Concern

Too Much in Ration: Ketosis / Milk Fever

Bacteria

E. Coli Up to 6 month + viable in soil

Does not survive as well on surface

Enters streams when manure runs off

Antibiotics

Animals DO NOT break them down. Excreted intact with the urine Low level resistance concerns

Biochemical Oxygen Demand

* A measure of how much oxygen is removed from a water body by the bacteria breaking down organic materials. (BOD)

Chemical Oxygen Demand (COD)* Oxygen required to break down

chemical compounds in water body.

Manure Basics

What is Manure? Urine, feces

Waste feed

Parlor water

Gray water (sinks, etc)

Manure Basics

How Much Manure Does a cow produce in a day? A week? A Month? A Year?

The Influence Of Milk Production On Daily Manure Production

0

50

100

150

200

250

0 5000 10000 15000 20000 25000 30000

Milk Production (RHA)

Man

ure

(lb

s/co

w/d

ay)

How Much Manure?

Typical Dairy Cow:148 lbs/day (18 gal)1036 lbs/week (124 gal)4440 lbs/month (531 gal)54020 lbs/year (6460 gal)

Does not include youngstock, other wastes

Rule of Thumb #1

One cow plus replacement plus wastewater = 10,000 gal/year

What is in manure?

NutrientsNitrogen, Phosphorus, PotassiumMicro nutrients (Sulfur, Boron, etc)

Whatever the cow eats that does not become milk or meat becomes manure.

If it’s in the feed, it’s in the manure.

Dairy Diet and Runoff Manure from 2 rations applied 1.28 and 0.48% P (rec is 0.34-0.38)

Runoff was 4x higher for high P diet Same lbs P applied

Runoff was 10x higher when manure rates were the same.

Ebeling et al, 2001

Dairy Diet Impacts Ave P in dairy ration is 0.47%

Gunderson, Keuning & Erb, 2001

NRC Recommendation is 0.32-0.38% P

Higher rates are due to belief that lower P reduces reproductive efficiency.

The Manure Paradox

Crops use N:P:K in a 3:1:2 ratio

Dairy manure is a 1:1:2 ratio (available)

Meet the crop’s N need = excess P

Meet the crop’s P need = buy N fert

Manure Nutrient Content - Dairy -

_____________________________________

N P2O5 K2O (surface/incorporated)

______________________Solid (lb/ton) 3 / 4 3 8

Liquid (lb/1,000 gal) 8 / 10 8 21_____________________________________

Crop Nutrient Removal

*recommended application rate. Note that these numbers vary by state/prov.

N P2O5 K2O

- - - - - - - - - lb/a/yr - - - - - - - -

Corn (160 bu/a) 160* 60 40

Corn silage (23 ton/a) 225 90 170

Soybean (40 bu/a) 115 35 40

Alfalfa (5 ton/a) 250 65 250

Reed canarygrass 250 125 325(5 ton/a)

Example of P2O5 Recommendations for Corn

Yield Goal Soil Test Levelbu/a Low Optimum High Ex.High

- - - - - - - - - - - - - - lb/acre - - - - - - - - - - - - - -

111-130 65 45 25 0

131-150 75 55 25 0

151-170 80 60 30 0

Corn Nutrient Need vs. Manure Nutrient Supply

Following a Nitrogen Strategy

lb/acre

Manure Application Rates

Nitrogen Strategy Maximum rates P and K in excess of crop need Efficient with time and labor Preferred when land is limited

Corn Nutrient Need vs. Manure Nutrient Supply Following a Phosphorus Strategy

lb/acre

Manure Application Rates

Phosphorus Strategy Low rates Need supplemental nitrogen Increased time and labor Need adequate acreage

Manure Nitrogen ContentTotal vs. AvailableSolid Manure

0

2

4

6

8

10

12

14

Dairy Beef Swine

Total N Available N

lb N/ton

Soil Test P Changes Slowly

Soil buffering capacity The amount of fertilizer needed to change

the soil test level by 1 ppm 18 lbs P2O5/acre = 1 ppm change in soil P

Time is required to either lower or raise soil test levels.

Soil Test P Changes Slowly- Example -

Soil test P = 75 ppm (EH) Track draw-down of P over a

CCOHHH rotation.

Soil Test P Changes Slowly- Example - Soil test P = 75 ppm (EH) Track draw-down of P over a CCOHHH rotation.

Corn @150 bu/a removes 55 lb P2O5/a/yr

Oats @ 100 bu/a removes 25 lb P2O5/a/yr

Alfalfa @ 5 tons/a removes 65 lb P2O5/a/yr

Removal of P2O5 over rotation = 330 lbs P2O5

Soil Test P Changes Slowly- Example - Soil test P = 75 ppm (EH) Track drawdown of P over a CCOHHH rotation. Removal of P2O5 over rotation = 330 lbs P2O5

Change in soil test P = 330 lb P2O5/18 = 18 ppm P

Soil Test P Changes Slowly- Example - Soil test P = 75 ppm (EH) Track drawdown of P over a CCOHHH rotation. Removal of P2O5 over rotation = 330 lbs P2O5

Change in soil test P = 330 lb P2O5/18 = 18 ppm P

Soil test P = 57 ppm (EH) after the 6-year rotation.

(75 ppm P - 18 ppm P = 57 ppm P)

Regulations

1972 Clean Water Act

Point vs. Non-Point Sources

Problem Not Yet Solved.

Regulatory Future Each Providence, State, County,

Township may be different. Future

Lower AU (animal unit) threshold for permit More phosphorus emphasis Future emphasis on bacterial / antibiotics /

odor concerns

Short term focus will be on P based nutrient management

Economics(Nitrogen @ $0.20/lb)

100 Cow Dairy Alfalfa N = $

1,200 (50 acres/yr @ 120 lbs N/a)

Manure N = $ 1,320

(22 tons/cow/year @ 3 lbs N/ton)

Total On-Farm N =$ 2,520

Economics(P2O5 @ $0.25/lb; K2O @ $0.13/lb)

100 Cow DairyManure P2O5 = $ 1,650 (22 tons/cow/year @ 3 lbs P2O5/ton)

Manure K2O = $ 2,288(22 tons/cow/year @ 8 lbs K2O/ton)

Total Manure P205 & K2O = $ 3,938

If You Are Going To Use Manure as a Fertilizer…

Treat It Like A Fertilizer!

Soil Test Phosphorus Variability from a Wisconsin Dairy Farm

Public Relations

Manure Handling and Application Odor control Real or perceived excessive rates Road spillage Traffic hazards & delays Spreading near water Cattle in water

Challenges of the Future:

Dairy Trends. Management: More cows, fewer farms. Realization by farmers that manure

management requires a cash investment. Manure’s Internet IPO: Lots of ideas now,

lots of broken ideas coming in a few years. Easiest to use / most farm-profitable techniques will remain.

Opportunities of the Future:

Every farm will have a nutrient management plan. Nitrogen – Phosphorus Pendulum Affiliated and independent consultants Site-specific research

Between 1992 and 2001, UWGB was the lead institution for mass balance research.

Farmers are searching for answers.

Manure is no longer considered the last item after everything else is done.

Farmers are searching for answers.

Manure is no longer considered the last item after everything else is done.

kevin.erb@ces.uwex.edukevin.erb@ces.uwex.edu