Nutrient Content of Poultry Litter Compost

Highly Pathogenic Avian Influenza (HPAI) has impacted more than 70 commercial poultry farm locations in four Ohio counties these past few months involving 14,668,251 birds. There has not been a new detection since March 6, 2025. This Ohio Department of Agriculture (ODA) site tracks the HPAI outbreaks in Ohio. https://agri.ohio.gov/divisions/animal-health/hpai/01-poultry

HPAI is considered a foreign animal disease that is thought to be brought to Ohio through migrating, wild birds.  As such, the ODA and United State Department of Agriculture (USDA) carry out initial response and containment activities on the affected sites as well as the surrounding area to manage the disease and prevent further spread. Although these poultry producers may have their Ohio livestock mortality composting certificates, the federal livestock and avian mortality disposal laws take precedent when a foreign animal disease is involved.

The predominant method of HPAI disposal is typically composting of the infected materials, which may include carcasses, manure/bedding, feed, and/or eggs (if a layer operation is involved). A premise must undergo appropriate disposal operations, in addition to many other requirements, prior to having their quarantine released.

Composting is the biological decomposition of organic material under controlled, aerobic conditions that can inactivate pathogens and convert mortalities into a nutrient-rich soil amendment. The compost can be used as a fertilizer.

Dealing with HPAI has been tough on all involved including the livestock producers and the businesses tied to livestock production in western Ohio. It has been a mammoth undertaking in sampling the flocks for the virus, depopulation of the infected birds, time spent in securing and transporting carbon amendments for compost piles, building the compost piles, sampling the compost piles for temperatures, turning the piles, cleaning and disinfecting the premise, and the transportation and land application of the finished compost.

Once the compost piles have met the time and temperature requirements for virus elimination and are released by the state, the compost can be land applied to fields. Producers are required to follow applicable state requirements for movement, distribution, and land application of mortality compost according to OAC 3745-560-230 and OAC 901:10-2-10. Requirements may include sampling and testing of the compost for a variety of parameters.

Poultry compost analysis results can vary for many reasons. These can include sampling error, size/age of the animals composted, newness of the bedding material, quality of the carbon amendments used in the composting process and the length of the composting period. Some compost piles will need additional grinding, screening or held longer for further composting simply due to the size and variability of the wood chips used in the composting process.

At the Conservation Tillage and Technology Conference last month the question was raised about the nutrient value of the HPAI compost piles in western Ohio. The following charts are the most current nutrient information we have available.

Iowa experienced a large outbreak of HPAI in 2016 and Table 1 shows the results of 43 turkey compost samples from 15 Iowa farms.

Table 1. 2015 Iowa Turkey Compost Samples. Average of 43 Samples from 15 Farms

HPAI struck a large commercial poultry laying farm in Defiance County, Ohio in the fall of 2022. In Table 2 are the nutrient testing results from the HPAI compost land applied in 2023.

Table 2. 2022 Defiance County, Ohio 78 Layer Compost Samples

In addition to the compost samples, regular poultry litter was sampled and land applied for the Defiance farm at the same time of the layer compost sampling.

Table 3 Defiance County, Ohio 21 Regular Poultry Litter Samples

Nearly all the HPAI compost piles in western Ohio have met the regulatory requirements for release and land application. Table 4 has the nutrient content from most of the turkey compost samples collected and sent for analysis. 

 Table 4. 2025 Mercer & Darke Counties 35 Turkey Compost Samples

Table 5 has the nutrient content of compost samples from layer farms collected and sent for analysis.

Table 5. 2025 Mercer and Darke Counties 26 Layer Compost Samples