Value of Poultry Manure Nutrients for Crop Production

Antonio Mallarino and John SawyerDepartment of Agronomy

Nutrients for Crop Production

• Corn almost always needs N.• P and K are needed for low-testing

soils and to maintain optimum levels.• Manure can be used to supply N, P,

K, and other nutrients. It may also improve physical soil properties by supplying organic matter.

• But excessive or badly applied manure can impair water quality.

Issues for Manure Nutrients Use

• Nutrient concentration variability.• N-P-K ratios and crop needs.• Manure nutrient availability shortly

after application.• Expensive storage and handling,

difficulties for uniform application.• Soil-test variability in manured fields.• Producer's doubts about its value.• State/federal regulations for its use.

N & P Concentration of Solid Manures

0

20

40

60

80

Swinegrowfinish

Dairy &Beef

Layers Broilers Turkey

N

P205

Table Values in Pm 1811

A. Rieck-Heinz

Poultry Manure Nutrients

• No organic K, all soluble inorganic.• Variable proportion of inorganic and

organic N, P, and S. Organic forms must be mineralized to be absorbed.

• Mineralization rates vary with the handling and application methods, climate, and field conditions.

• Nutrient availability immediately after application is difficult to predict.

Ammonium - Organic N in Manures

0 20 40 60 80 100

Swine PitSwine Lagoon

Beef Feedlot

Liquid BeefComposted

Poultry

% Distribution

Ammonium Organic

Manure Nitrogen Availability

• Guidelines for 1st-year N availability compared with fertilizer (Pm 1811):- beef and dairy: 30 to 40%- poultry: 65%- swine: 100%

• N volatilization:- incorporation within 24 hrs 0.95- incorporation after 24 hrs 0.80- no incorporation at all 0.70

Phosphorus in Animal Manures

• 40 to 95% inorganic P, simple to complex compounds, highest values are for liquid swine manure.

• Phytase enzyme feeding may reduce total P by 25 to 35%.

• P water solubility varies a lot but isn’t a good index of availability.

• Iowa: 60% availability in low-testing soils and 100% for maintenance.

Poultry Manure Nutrients Utilization Project

Antonio MallarinoJohn SawyerDaniel KaiserDorivar Ruiz-DiazDavid WittryBrett AllenMazhar HaqDaniel Barker

18 producers' fields2004, 2005, and 200614 countiesLayers, turkeys, broilers

Poultry Manure Field Resehararch

Manure strips 01 2

Reps 1 2 3

2 20 0 11

3 manure rates applied to strips using farmer's or applicator's equipment.

4 N fertilizer rates and 4 P fertilizer rates to small plots. Uniform K rate and N or P rates as appropriate across P or N small plots.

Measured manure nutrients, early corn growth, grain, and soil-test values after harvest.

Manure Total N ConcentrationM

anur

e N

itrog

en (l

b N

/ to

n)

0

20

40

60

80

100

120PM 1811Tested Values

Layers TurkeyBroilers

Range

Manure Total P ConcentrationM

anur

e P

(lb P

2O5

/ ton

)

0

20

40

60

80

100

120 PM 1811Tested Values

Layers TurkeyBroilers

Range

Poultry Manure Nutrient Variation

Poultry Manure Sample Analyses (As-Is Basis)

-40

-30

-20

-10

0

10

20

30

40

0 10 20 30 40 50 60 70 80 90 100

Average Site Analysis (lb N, P2O5, or K2O/ton)

Indi

vidu

al S

ampl

e D

iffer

ence

Fro

m S

ite

Ave

rage

(lb/

ton)

Total-NTotal-PTotal-K

All Site AverageN: 63 lb N/tonP: 63 lb P2O5/tonK: 41 lb K2O/ton(18 sites, 108 samples)

Corn Response to Poultry Manure 7 to 68 bu/acre Response. Average 41 bu/acre

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18

Cor

n Yi

eld

(bu/

acre

)

60

80

100

120

140

160

180

200

220

2004 20062005

No manure Low manureHigh manure

Yields and Manure or Fertilizer NAverages Across All Responsive Sites

N Fertilizer Rate (lb N/acre)0 50 100 150

Yie

ld R

espo

nse

(bu/

acre

)

0

20

40

60

80

No manure

Manure high

Manure low

Low : 111 lb N/acre (44-172)High: 225 lb N/acre (104-336)

Average Manure-N Rates

High Uniform P and K Rates Applied

Canopy Greenness with SPAD MeterAverages Across All Responsive Sites

N Fertilizer Rate (lb N/acre)0 50 100 150

Can

opy

Gre

enne

ss R

eadi

ng

0

2

4

6

8

10

12

14

No manure

Manure high

Manure low

Low : 111 lb N/acre (44-172)High: 225 lb N/acre (104-336)

Average Manure-N Rates

High Uniform P and K Rates Applied

Late Spring Soil Nitrate Test

Soil Nitrate-N (ppm)0 10 20 30 40 50 60

Cor

n Y

ield

Res

pons

e (b

u/ac

re)

0

20

40

60

80

100

No manure

High manure rateLow manure rate

A good test only to tell whenwhen no extra N is needed

Poultry Manure N and Timing

Holmes and Rueber, ISU

Cor

n G

rain

Yie

ld (b

u/ac

re)

100

110

120

130

140

150

160

170

180

190

200

210

Control

82 lb Manure N

Winter

135 lb NSpring Urea

Spring

164 lb Manure N

Winter

Spring

Egg Layers ManureNorthern Research Farm3-year Averages

Recent Research: Poultry Manure N

• The N availability compared with fertilizer N is on average 50 to 60%.

• N volatilization:- Incorp. within 24 hrs 0.95 - 0.99- Delayed or no incorp. 0.70 - 0.80

• Long-term manure application increases soil organic matter and may increase N mineralization rates and N supply for crops.

Soil P Buildup After HarvestAverage Buildup: Low Rate = 14 ppm High Rate = 30 ppm

1 2 3 4 5 6 1 2 3 4 5 6 1 2 3 4 5 6

Soil

P B

uild

up (p

pm)

0

10

20

30

40

50

60

70

2004 20062005

Low manure rate High manure rate

Low : 136 lb P2

O5

/acre (90-198)

High: 258 lb P2

O5

/acre (168-346)

Low: 2.0 ton/acre (1.5-2.3)

High: 3.8 ton/acre (2.4-4.6)

Poultry Manure as a P SourceAverage Across Fields with Yield Response to Fertilizer or Manure P

P Fertilizer Rate (lb P2O5/acre)0 50 100 150

Cor

n Yi

eld

Res

pons

e (b

u/ac

re)

0

5

10

15

20

25

No Manure

Low Manure

High Manure

Low : 136 lb P2O5/acre (90-198)High: 258 lb P2O5/acre (168-346)

Manure and Manure-P Rates

Low: 2.0 ton/acre (1.5-2.3)High: 3.8 ton/acre (2.4-4.6)

Uniform N and K Fertilizer Applied

a

aa

aa

a

b

c

bb

Poultry Manure P and Early GrowthAverages Across All Fields

P Fertilizer Rate (lb P2O5/acre)0 50 100 150

Cor

n Ea

rly G

row

th (g

/pla

nt)

2.6

2.8

3.0

3.2

3.4

3.6

3.8

4.0

4.2

4.4

No Manure

Low Manure

High Manure

Summary: Poultry Manure P

• The P availability is higher than we thought: is 90 to 100%.

• Uncertainty on poultry manure P availability isn't as important as for N because much P is applied even by applying ½ of the N needed by corn.

• Major issues with poultry manure P are soil P buildup and uniformity of application for wet manures.

Manure N-P Ratios and Crop Needs

• N-based manure application often results in soil P build-up over time.

• Corn-soybean rotation:- Dairy & beef: small or no P buildup- Swine: small or no P buildup, may

be short of P when phytase is used.- Poultry: large P buildup, larger for

egg layers, less with phytase.• Corn after corn: very large buildup.

Egg layers manure assuming 35 lb of N and80 lb of P205 / ton:

Needs N-Based AppliedCrop N P205 Manure P205

180 bu Corn 150 lb 68 lb 4.3 ton 344 lb

60 bu Beans 0 lb 48 lb none 0 lb

Total: 116 lb 344 lb

Total P by applying just 1/2 of N need (75 lb) 172 lb

N-Based Egg Layers ManureCorn-Soybean Rotation P Need and Applied P

Large P build up, enough for 3 years

Egg layers manure assuming 35 lb of N and50 lb of K20 / ton:

Needs N-Based AppliedCrop N K20 Manure K20

180 bu Corn 150 lb 54 lb 4.3 ton 215 lb

60 bu Beans 0 lb 90 lb none 0 lb

Total: 144 lb 215 lb

Total K by applying just 1/2 of N need (75 lb) 107 lb

N-Based Egg Layers ManureCorn & Soybean K Needs and Applied K

Insufficient K (75%) for the rotation

Maximizing Manure N Use Efficiency

• Use manure analysis but be aware of high variability.

• Mineralize the most of organic N:- fall application allows more time but puts

inorganic nitrate-N at greater risk of loss

• Minimize ammonium volatilization:- immediate incorporation into the soil

• In-season tests for additional N:- late-spring soil nitrate and emerging tools

such as aerial photos and sensors.

Maximizing Manure P & K Use

• Use manure and soil analyses but be aware of high variability.

• Full N-based poultry manure rates apply excess P and K (for 2 or 3 crops), look at P Index over time.

• Phytase feeding reduces manure P. Good to balance nutrient content and allows for higher manure application rates and more use of manure N.

Nutrient Availability in Practice

• Manures are heterogeneous materials often difficult to handle.- high nutrient variability, difficult

application of uniform rates, high soil-test variability in manured soils

• These factors introduce much more uncertainty than for fertilizers and may reduce the usually assumed efficiency of manure nutrients.