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Poultry Manure as a Fertilizer Source


Table of Contents


Nutrient Composition and Sampling Procedure

Nutrient Availabilities

Application Rate

Timing and Uniformity of Manure Applications

Acreage Requirements for New Facilities

Value of Manure

Land Application Worksheet

 


Prepared by
J. P. Zublena, Extension Soil Science Specialist; J. C. Barker, Extension Agricultural Engineering Specialist; and T. A. Carter, Extension Poultry Science Specialist

Published by
North Carolina Cooperative Extension Service

Publication AG-439-5
Revised May 1993 (MOC)

Last Web Update:
December 1997 (DBL)

Poultry manure is an excellent source of nutrients and can be incorporated into most fertilizer programs. Those using manures must practice sound soil fertility management to prevent nutrient imbalances and associated animal health risks, as well as surface-water and groundwater contamination. The key to successful management is to match the nutritional requirements of the crop with nutrients available in the manure. The value of poultry manure varies not only with its nutrient composition and availability, but also with management and handling costs.

 

Nutrient Composition and Sampling Procedure

The nutrient composition of poultry manure varies with the type of bird, the feed ration, the proportion of litter to droppings, the manure handling system, and the type of litter. Consequently, all manures should be sampled and analyzed for specific nutrient content before you apply them to the land. Waste samples, from North Carolina, can be analyzed for $4 by the North Carolina Department of Agriculture (NCDA), Agronomic Division , Plant Analysis Lab, 4300 Reedy Creek Road, Raleigh, NC 27607-6465. Other qualified private laboratories can also perform the analysis (fees vary).

Collecting a representative manure sample is essential to reliable nutrient analysis. The nutrient value of litter varies greatly within the poultry house. To reduce sample variability, collect subsamples of broiler, turkey, and duck litter in 6 to 12 areas of the house. Samples taken around waterers, feeders, and brooders should be proportionate to the space these areas occupy in the house. At each location, collect litter by digging an area down to the earth; be careful, however, not to include soil. Place the subsamples in a plastic bucket, mix thoroughly, and put 2 to 3 pounds of the mixture in a sample container. Samples from stockpiled litter should be taken from at least 6 locations around the pile, all at depths of at least 18 inches. Subsamples should be mixed and submitted as suggested for litter from poultry houses.

To increase sample uniformity in poultry manure slurries and lagoon sludges, stir them before sampling. Within an anaerobic lagoon, liquids are relatively uniform above the sludge zone; nevertheless, take several subsamples and combine them.

If you cannot have the manure analyzed, use the mean nutrient values for your specific type of poultry manure found in Tables 1 through 4. Table 5 gives the average values for the secondary and micronutrients ordinarily listed in the manure analysis report.

When using mean values for manure nutrient composition, exercise caution to avoid over- or under fertilization. Also, after several years, elements such as copper or zinc may accumulate and reach very high levels. To avoid these problems, take an annual plant tissue and a biennial soil sample to monitor nutrient levels.

Table 1. Average Nutrient Composition of Broiler Manures
Manure Type Total
N
Ammoniun
NH4+-N
Phosphorus
P2O5
Potassium
K2O
  lb/ton
Fresh (no litter) 26 10 17 11
Broiler house litter1 72 11 78 46
Roaster house litter1 73 12 75 45
Breeder house litter1 31 7 54 31
Stockpiled litter1 36 8 80 34
1Annual manure and litter accummulation; typical litter base is sawdust, wood shavings, or peanut hulls.
Source: Biological and Agricultural Engineering Department, NCSU.

 

Table 2. Average Nutrient Composition of Layer Manures
Manure Type Total
N
Ammonium
NH4+-N
Phosphorus
P2O5
Potassium
K2O
  lb/ton
Fresh (no litter) 26 6 22 11
Undercage scraped1 28 14 31 20
Highrise stored2 38 18 56 30
  lb/1,000 gallons
Liquid slurry3 62 42 59 37
Anaerobic lagoon sludge 26 8 92 13
  lb/acre-inch
Anaerobic lagoon liquid 179 154 46 266
1Manure collected within two days.
2Annual manure accumulation on unpaved surfaces.
3Six to 12 months' accumulation of manure, excess water usage, and storage-surface rainfall surplus; does not include fresh water for flushig
Source: Biological and Agricultural Engineering Department, NCSU.

 

Table 3. Average Nutrient Composition of Turkey Manures
Manure Type Total
N
Ammonium
NH4+-N
Phosphorus
P2O5
Potassium
K2O
  lb/ton
Fresh (no litter) 27 8 25 12
Brooder house litter1 45 9 52 32
Grower house litter2 57 16 72 40
Stockpiled litter3 36 8 72 33
1Based on cleanout after each flock.
2Based on annual cleanout after full production.
3Based on annual house accumulation removed to uncovered stockpile to be spread within six months.
Source: Biological and Agricultural Engineering Department, NCSU.

 

Table 4. Average Nutrient Composition of Duck Manures
Manure Type Total
N
Ammonium
NH4+-N
Phosphorus
P2O5
Potassium
K2O
    lb/ton
Fresh (no litter) 28 5 23 17
House litter1 19 3 17 14
Stockpiled litter2 24 5 42 22
1Annual manure and litter accumulation; typical litter base is wood shavings.
2Annual house accumulation removed to uncovered stockpile to be spread within six months.
Source: Biological and Agricultural Engineering Department, NCSU.

 

Table 5. Average Secondary and Micronutrient Content of Poultry Manures
Manure Type Ca Mg S Na Fe Mn B Mo Zn Cu
  lb/ton
Layer
Undercage scraped 43.0 6.1 7.1 4.5 0.52 0.27 0.050 0.00390 0.32 0.036
Highrise stored 86.0 6.0 8.8 5.0 1.8 0.52 0.046 0.00038 0.37 0.043
Broiler Litter
Broiler house 41.0 8.0 15.0 13.0 1.3 0.67 0.054 0.00085 0.63 0.45
Roaster house 43.0 8.5 14.0 13.0 1.6 0.74 0.049 0.00082 0.68 0.51
Breeder house 94.0 6.8 8.5 8.6 1.3 0.57 0.035 0.00048 0.52 0.21
Stockpiled 54.0 8.0 12.0 6.2 1.5 0.59 0.041 0.00069 0.55 0.27
Turkey Litter
Brooder house 28.0 5.7 7.6 5.9 1.4 0.52 0.047 0.00081 0.46 0.36
Grower house 42.0 7.0 10.0 8.4 1.3 0.65 0.048 0.00092 0.64 0.51
Stockpiled 42.0 6.8 9.5 6.4 1.5 0.62 0.047 0.00095 0.56 0.34
Duck Litter
Duck house 22.0 2.7 3.1 2.8 0.98 0.31 0.021 0.00040 0.26 0.056
Stockpiled 27.0 4.4 5.6 8.8 1.2 0.47 0.030 0.00030 0.47 0.050
  lb/1,000 gallons
Layer
Liquid slurry 35.0 6.8 8.2 5.3 2.9 0.42 0.040 0.018 0.43 0.08
Lagoon sludge 71.0 7.2 12.0 4.2 2.2 2.3 0.082 0.014 0.80 0.14
  lb/acre-inch
Layer
Lagoon liquid 25.0 7.4 52.0 51.0 2.0 0.24 0.37 0.020 0.70 0.19

 

Nutrient Availabilities

Except for nitrogen, the availability of most nutrients in poultry manures is fairly consistent. Nitrogen can occur in several forms, each of which can be lost when subjected to different management or environmental conditions.

Nitrogen in poultry wastes comes from uric acid, ammonia salts, and organic (fecal) matter. The predominant form is uric acid, which readily transforms to ammonia (NH3), a gaseous form of nitrogen that can evaporate if not mixed into the soil. When it is thoroughly mixed, the ammonia changes to ammonium (NH4+), which can be temporarily held on clay particles and organic matter. Thus, soil mixing can reduce nitrogen losses and increase the amount available to plants.

Table 6 lists the first-year nutrient availability coefficients for various poultry manures. Determine the available nutrients by multiplying these values by the nutrient composition values listed on the waste analysis report or in Tables 1, 2, 3, and 4. The NCDA's Agronomic Division calculates available nutrients and lists them in its report.

 

Table 6. First-Year Nitrogen Availability Coefficients for Different Poultry Manures
ManureType Injection Soil Incorporation 2 Broadcast 3 Irrigation 4
  P2O5 and K2O availability coefficients
All manure types 0.8 0.8 0.7 0.7
  N availability coefficient
All poultry litters5 0.6 0.5
Layers (no litter) 0.6 0.4
Layer anaerobic
lagoon sludge
0.6 0.6 0.4 0.4
Layer anaerobic
liquid slurry
0.8 0.7 0.4 0.3
Layer liquid
lagoon
0.9 0.8 0.5 0.5
1Manure injected directly into soil and covered immediately.
2Surface-spread manure plowed or disked into soil within two days.
3Surface-spread manure uncovered for one month or longer.
4Sprinkler-irrigated liquid uncovered for one month or longer.
5Includes in-house and stockpiled litters.

 

Application Rate

Land application rates are generally determined by matching the available nitrogen or phosphorus content of the waste to the nutrient requirements of the crop. In most cases, nitrogen requirements determine the application rate, unless the area is designated "nutrient sensitive" and indicates that phosphorus movement off-site can lead to eutrophication of surface waters. In nondesignated areas, phosphorus movement can be adequately controlled with conservation measures such as grass field borders, grassed waterways, contour planting, and reduced tillage, which minimize soil and residual manure movement. Leaching of phosphorus is extremely limited on mineral soils and should not contribute to groundwater contamination.

Nitrogen recommendations for various crops are listed in Table 7. Use these rates as guidelines with realistic yield capabilities for the crop and field. With feed and forage crops, excessive manure application can produce high nitrate concentrations, which can harm livestock (through nitrate poisoning) and promote nutrient imbalances that may lead to grass tetany. If loading rates are to be based on phosphorus, apply the amount suggested by soil-test recommendations. Because the manure may not supply adequate amounts of all the other nutrients required by the crop, be sure to take a soil test and, if necessary, supplement with commercial fertilizer.

 

Table 7. Nitrogen Fertilization Guidelines
Commodity lb N/RYE 1
Corn (grain) 1.0 to 1.25 lb N/bu
Corn (silage) 10 to 12 lb N/ton
Cotton 0.06 to 0.12 lb N/lb lint
Sorghum (grain) 2.0 to 2.5 lb N/cwt
Wheat (grain) 1.7 to 2.4 lb N/bu
Rye (grain) 1.7 to 2.4 lb N/bu
Barley (grain) 1.4 to 1.6 lb N/bu
Triticale (grain) 1.4 to 1.6 lb N/bu
Oats 1.0 to 1.3 lb N/bu
Bermudagrass (hay2,3) 40 to 50 lb N/dry ton
Tall fescue (hay2,3) 40 to 50 lb N/dry ton
Orchardgrass (hay2,3) 40 to 50 lb N/dry ton
Small grain(hay2,3) 50 to 60 lb N/dry ton
Sorghum-sudangrass (hay2,3) 45 to 55 lb N/dry ton
Millet (hay2,3) 45 to 55 lb N/dry ton
Pine trees4 40 to 60 lb N/acre/year
Hardwood trees4 70 to 100 lb N/acre/year
1RYE = Realistic Yield Expectation
2Annual maintenance guidelines
3Reduce N rate by 25 percent when grazing.
4On trees less than 5 feet tall, N will stimulate undergrowth competition.

In addition to monitoring nutrients, be sure to maintain an adequate soil pH, which will help to maximize crop yields and nutrient availability and promote the decomposition of organic matter. The biological conversion of organic matter to nitrate is an acid-forming process. Take annual or biennial soil samples to monitor pH changes. When livestock wastes are applied at agronomic rates, high salinity (excess salt) has not been a problem, given normal amounts of rainfall in North Carolina.

A worksheet to help you determine land application rates is included at the end of the text.

 

Timing and Uniformity of Manure Applications

To minimize nitrogen losses, apply manure as near as possible to planting time or to the crop growth stage during which nitrogen is most needed. Surface water and groundwater contaminations are greater in areas of high rainfall and when manures for spring crops are applied in fall or winter. For coarse-textured soils, manures should be applied frequently and at low rates throughout the growing season because such soils have a high water infiltration rate and a low ability to hold nutrients. Unused nitrogen can therefore be lost by leaching.

Exercise caution when applying lagoon liquid by irrigation on crops undergoing stress (for example, corn during an extended drought). A heavy coating of manure solids on the leafy vegetation can cause ammonia burn. Except in extreme cases, this damage is usually short term and does not significantly reduce yields. With concentrated lagoon liquids, use several small applications rather than one large dose.

Whether poultry waste is applied by manure spreaders or irrigation systems, you must apply it uniformly. A lack of uniformity leads to nutrient excesses and deficiencies, lower yields, and variable crop moisture at harvest time.

 

Acreage Requirements for New Facilities

Whenever manure or lagoon liquid samples are available for analysis, they should be used to determine application rates and acreage requirements. When you are planning new facilities, however, the average values can help determine approximate acreage requirements for a poultry operation of a given size. Table 8 gives minimum acreage requirements for various nitrogen fertilization rates. This table can be used to estimate the minimum acreage required to use all of the manure.

Suppose that a producer is interested in building two broiler houses with a combined 50,000 bird capacity/growout. The producer is planning to spread this litter on a bermudagrass hay field capable of producing 6 dry tons per acre. From Table 7, the bermudagrass will require 300 lb nitrogen per acre (6 tons x 50 lb N/dry ton). How many acres of bermudagrass would be needed for the entire year's waste? Using Table 8, under surface broadcast column 300, we find that each 1,000-bird capacity would require 0.65 acre for land application of broiler litter. For a 50,000-bird growout operation (0.65 x 50), the producer would need 32.5 acres for a year's worth of litter.

Table 8. Minimum Amount of Land Needed to Apply Poultry Manure as a Nitrogen Fertilizer Source (Based on the Nitrogen Rate Required by the Crop)
Manure Handling and Production Unit Soil Incorporated1 Surface Broadcast2
lb N/acre/year
100 200 300 400 100 200 300 400
Annual acres/1,000 bird single capacity
Layer
Undercaged scraped 4.80 2.40 1.60 1.20 3.00 1.50 1.00 0.75
Highrise scraped 4.30 2.15 1.43 1.07 2.60 1.30 0.87 0.65
Liquid manure/slurry 6.70 3.35 2.23 1.68 4.00 2.00 1.33 1.00
Anaerobic lagoon sludge 0.71 0.35 0.24 0.18 0.56 0.28 0.19 0.14
Anaerobic lagoon liquid 0.87 0.43 0.29 0.22 0.84 0.42 0.28 0.21
Broiler Litter
Broiler house 2.40 1.20 0.80 0.60 1.96 0.98 0.65 0.49
Roaster house 4.30 2.15 1.43 1.08 3.60 1.80 1.20 0.90
Breeder house 4.70 2.35 1.57 1.18 3.20 1.60 1.07 0.80
Stockpiled 1.20 0.60 0.40 0.30 0.92 0.46 0.31 0.23
Turkey Litter
Brooder house (poult) 1.40 0.70 0.47 0.35 1.08 0.54 0.36 0.27
Breeder house 8.10 4.05 2.70 2.02 5.60 2.80 1.87 1.40
Grower hen house 5.70 2.85 1.90 1.43 4.00 2.00 1.33 1.00
Grower tom house 8.60 4.30 2.87 2.15 6.00 3.00 2.00 1.50
Stockpiled
Poult 0.94 0.47 0.31 0.23 0.76 0.38 0.25 0.19
Hen 3.00 1.50 1.00 0.75 2.40 1.20 0.80 0.60
Tom 4.50 2.25 1.50 1.13 3.60 1.80 1.20 0.90
Duck Litter
Duck house 3.00 1.50 1.00 0.75 2.20 1.10 0.73 0.55
Stockpiled 1.50 0.75 0.50 0.38 1.08 0.54 0.36 0.27
1Incorporated within two days
2Not incorporated for at least 1 month

 

Value of Manure

When comparing manure to commercial fertilizers, convert total manure nutrients to available nutrients by using the availability coefficients. Consider the following example. Analysis of the available nitrogen, phosphorus (P2O5), and potassium (K2O) content in a broiler litter sample that will be incorporated shows that it contains 43 pounds of nitrogen per ton, 62 pounds of phosphate per ton, and 37 pounds of potash per ton. If the current fertilizer prices for nitrogen, phosphate, and potash were as follows: $0.23 per pound of nitrogen; $0.22 per pound of phosphate; and $0.12 per pound of potash as potassium chloride. One ton of broiler litter would be worth the following:

(43 x $0.23) + (62 x $0.22) + (37 x $0.12) = $27.97 per ton

This value would not cover hauling, handling, or application costs, nor would it include the value of other essential nutrients available in the manure. In addition, it assumes that the soil test has recommended each nutrient, when, in fact, many may not be needed. Nutrients not needed should not be considered when you assess the manure's value.

 

Table 9. Estimated Residual Nitrogen Provided by Legumes Grown in Rotation
Legume1 Residual Nitrogen Available
lb/acre
Alfalfa2 80 to 100
Hairy vetch2 80 to 100
Crimson clover2 60 to 75
Austrian winter pea2 50 to 60
Soybeans3 harvested for seed 15 to 30
Peanuts3 harvested for seed 20 to 40
1Assumes good stand.
2Killed before planting current spring crop.
3Legume planted in previous year or season. More nitrogen available if fall-planted crop immediately follows legume; less nitrogen available with spring-planted crop.

 

Land Application Worksheet

Farmer Jones is preparing to spread broiler litter on a field and incorporate it within two days to supply nutrients to his corn crop. Last year, he grew soybeans in the field.

His corn-yield goal is 140 bushels per acre, and he has decided to apply the equivalent of 140 pounds of nitrogen per acre (Table 7). His land is not subject to erosion, is not in a nutrient-sensitive watershed, and has grassed borders and waterways to further reduce the potential of runoff.

Farmer Jones used a starter fertilizer on his corn crop at a rate to supply 10 pounds of nitrogen per acre and 34 pounds of phosphorus per acre. He intends to supply the rest of his nitrogen needs by applying broiler litter with a litter spreader and incorporating it within two days.

How much litter does he need to spread in order to meet the nitrogen needs of his corn crop? Will he need to supplement the crop with additional potash or phosphate to satisfy his soil-test recommendations of 50 pounds per acre of each nutrient? The answers are given in the following worksheet. Use Table 9 to estimate available nitrogen carry-over from legumes.

Worksheet: Determining the Nutrient Needs of Your Crop
  Example Your Farm
1. Crop to be grown corn ______
 
2. Total nutrients required    
a. N (Table 7) (lb/acre) 140 ______
b. P2O5 (soil test) (lb/acre) 50 ______
c. K2O (soil test) (lb/acre) 50 ______
     
3. Pounds of starter or preplant fertilizer used    
a. N (lb/acre) 10 ______
b. P2O5 (lb/acre) 34 ______
c. K2O (lb/acre) 0 ______
 
4. Residual N credit from legumes (Table 9) (lb/acre) 20 ______
 
5. Net nutrient needs of crop (lb/acre)    
Nitrogen: total need (item 2a) minus additional N from starter (item 3a) minus legume residual (item 4)

a. N: 140 -10 - 20 (lb/acre)
110 ______
Phosphorus: total need (item 2b) minus additional nutrients from starter (item 3b)

b. P2O5: 50 - 34 (lb/acre)
16 ______
Potassium: total need (item 2c) minus additional nutrients from starter (item 3c)

c. K2O: 50 - 0 (lb/acre)
50 ______
 
6. Nutrient totals in manure. If analysis report already gives available nutrients, skip this item.    
a. Total N (Tables 1 to 4 or waste samples) (lb/ton) 72 ______
b. P2O5 (lb/ton) 78 ______
c. K2O (lb/ton) 46 ______
 
7. Nutrients available to crop (items 6a, 6b, and 6c) times availability coefficients (Table 6). If analysis report already gives available nutrients, fill in those numbers.    
a. Available N: 72 x 0.6 (lb/ton) 43.2 ______
b. Available P2O5: 78 x 0.8 (lb/ton) 62.4 ______
c. Available K2O: 46 x 0.8 (lb/ton) 36.8 ______

 

Worksheet: Rate of Manure to Apply
  Example Your Farm
8. Application rate to supply priority nutrient    
a. Priority nutrient Nitrogen ______
b. Amount of priority nutrient needed (lb/acre from item 5a) 110 ______
c. Rate of manure needed to supply priority nutrient (item 8b) divided by (item 7a): 110/43.2 (tons/acre) 2.55 ______
 
9. Pounds per acre of all nutrients supplied at the application rate required to meet the needs for the priority nutrient. For each nutrient, enter the available nutrients (items 7a, 7b, and 7c) times manure rate (item 8c)    
a. N supplied: 43.2 x 2.55 (lb/acre) 110 ______
b. P2O5 supplied: 62.4 x 2.55 (lb/acre) 159 ______
c. K2O supplied: 36.8 x 2.55 (lb/acre) 94 ______
     
10. Nutrient balance: net nutrient need (-) or excess (+) after application of manure at calculated rate. Subtract the net nutrient needs of the crop (items 5a, 5b, and 5c) from the nutrient rate applied (items 9a, 9b, and 9c).    
a. N balance: 110 -110 (lb/acre) 0 ______
b. P2O5 balance: 159 -16 (lb/acre) +143 ______
c. K2O balance: 92 - 50 (lb/acre) +44 ______
 
Note: Calculation format modified from Pennsylvania Department of Environmental Resources, Field Application of Manure, October 1986.

 

The authors wish to acknowledge the assistance and cooperation of the North Carolina Department of Agriculture's Agronomic Division in the analysis of samples and the development of the data used in this publication.