Recycling manure and compost: on-farm or take it away

Manure is a valuable source of organic matter and nutrients for gardens and crops. Manure should be applied to crops, pastures, and gardens based on plant nutrient needs. Applying too much of it, especially at the wrong time of year, can increase pollution risks.

- Value of Manure

- Manure with bedding

- Spreading manure and compost on-farm

- Options for taking manure off-farm

Photo courtesy of the Mid-Atlantic Equine Pasture Initiative.

 

 

 

Value of Manure

Manure is often expressed in terms of total nitrogen (N), "plant available" phoshorus (P2O5) and "plant available" potassium (K2O).

About 50% of manure N is in an organic form that breaks down slowly over time. The other 50% is readily available to plants, however, a significant portion of that available N is lost to volatilization or "gasing off" due to how it is stored and then applied to the land.

About 80 - 100% of the manure P205 and 85 - 100% of the K20 is available to plants once applied.

Average Nutrient Content of Manure in pounds per ton.
Book Values taken from Nutrient Recommendations for Field Crops in Vermont, University of Vermont Extension, 2004.

Animal	N lbs./ton	P2O5 lbs./ton	K2O lbs./ton
Dairy solid	9	4.5	7
Beef cattle	12	6	12
Swine	14	11	11
Sheep	23	8	20
Horse	9	6	11
Poultry (layers)	50	50	34

Back to top

Manure with bedding

Most small acreage livestock manure contains a fair amount of bedding and/or feed waste mixed in. Wood shavings or sawdust are a very common bedding material.

Manure with lots of wood shavings and sawdust can actually deplete the soil of nitrogen when applied to crops and gardens. This is because of the high levels of carbon contained in the wood products - the carbon to nitogen ratio or C:N ratio of wood shavings or sawdust is typically 500:1. As the carbon breaks down, it can deplete the soil of nitrogen.

Composting is a good option for manure with lots of bedding. It produces a stable, soil-like product that is free of weed seeds and pathogens when done correctly.

Visit our composting page for more information.

Finished compost. Photos courtesy of the Mid-Atlantic Equine Pasture Initiative.

Back to top

 

Spreading manure or compost on-farm

There are a variety of small ground driven manure spreaders that can be towed with an ATV or small garden tractor.

They range in capacity from 25 to 75 bushels (1 to almost 3 cubic yards) and range in price from just under $1,000 to over $2,500. Check with your local farm equipment supply store or do an internet search on small ground driven manure spreaders.

 

When spreading manure or compost on-farm:

1) Keep records of the manure or compost you apply - when, where, how much.

2) Take soil tests to determine crop nutrient needs.

UCONN Soil Testing Lab - download order form

UMASS Soil Testing Lab - download order form

Manure and compost tests can provide the actual nutrient value of your manure. Otherwise, book values for manure nutrient content can be obtained from the USDA NRCS or various University Extension Offices (see University of Vermont Extension book values above). Compost should be tested at a laboratory.
Penn State Manure Testing Program - download order form
UMASS Compost Testing - download order form

 

3) For annual gardens and crops, turn or "incorporate" the manure into the soil immediately after spreading to conserve nutrients and reduce potential losses due to runoff and volatilization (gasing off into the air).

If manure is applied to annual cropland in the Fall, consider planting a winter cover crop to control erosion and take up additional nutrients, minimizing nutrient losses.

 

 

4) Manure or compost can also be spread thinly and evenly over grasslands immediately after hay cuttings or mowing. If applying to pastureland, it is important to spread the manure about one month before a grazing cycle. Smothering of grasses can occur if the manure is applied too thickly or when the grasses are taller.

Parasite eggs in uncomposted manure may cause an infestation problem on pastures. Maintain a good de-worming program for your animals.

 

5) Avoid spreading manure during winter months and on frozen, snow-covered and muddy ground. Late fall through mid-Spring is a key period where properly managed manure storage areas are needed.

 

 

6) When manure or compost is applied to land on a regular basis, phosphorus levels can build up to an excessive level in the soil. It depends on how much you spread and the crops being grown.

When soil tests indicate very high phoshorus levels, avoid spreading manure and supplement with nitrogen and potassium as needed. When manure is applied to satisfy crop phoshphorus needs, nitrogen and potassium often need to be supplemented with other fertilizer sources.

Phosphorus free fertilizers.

7) Nitrogen is very soluble and mobile. It often volatilizes into the air, or can leach into groundwater when applied at rates greater than the plant can use. When it comes to nitrogen, more is not better.

Once the plant uses what it needs, any excess nitrogen will be lost to the air and water resources, increasing pollution risk and wasting valuable money. Heavy rains or excessive irrigation can also increase the risk of nitrogen leaching - robbing it from the plants.

Liquid manure being injected and incorporated to conserve nutrients and reduce potential losses due to volatilization, leaching and runoff.

View this fact sheet on Nutrient Management - Simplified for more information. (National Livestock and Poultry Environmental Stewardship, Small Farms Fact Sheets.)

Back to top

Options for taking manure off-farm

When you have a surplus of manure and nutrients and/or lack the land and equipment to spread the manure, we need to consider taking the manure to a location that can use it. Here are some options:

Back to top