Part six of a six-part series on compost utilization and management on farms.
The controlled biological decomposition of organic matter results in compost. Therefore, by definition, manure that is not managed by generally accepted compost production standards cannot be called compost. At best, it is decomposing manure.
Uses and benefits of compost
Compost has many uses and benefits in a cropping system if proper application is followed. For example, compost encourages the formation of appropriately sized soil aggregates, which protect the soil from erosion and compaction. Compost also enhances soil fertility through the slow release of macro- and micro-nutrients, as well as improving the availability of nutrients to growing crops. Most importantly, compost helps support living biological systems by imparting soil with beneficial microorganisms that suppress or control soil-borne plant pathogens. These suppressive qualities occur in compost made with specific feedstocks for specific cropping systems. Feedstocks, in this context, refer to the organic matter used to supply the carbon and nitrogen necessary for compost production. Examples of carbon feedstocks include sawdust and straw. Examples of nitrogen feedstocks include manure and fresh grass clippings.
What does it mean to have Right-to-Farm coverage?
The Michigan legislature passed into law the Michigan Right to Farm (RTF) Act (Act 93 of 1981). The Michigan RTF Act requires the establishment of Generally Accepted Agricultural Management Practices (GAAMPs). These practices are written to provide uniform, statewide standards and acceptable management practices based on sound science. On a livestock farm where manure is produced, these practices are implemented through a Manure Management Systems Plan (MMSP) found in the GAAMPs for Manure Management and Utilization (commonly referred to as the Manure GAAMPs). A farmer complies with the intent of the Michigan Right to Farm Act when a MMSP is developed, implemented, and sufficient documentation is provided to prove the plan was followed.
As an increasing number of farmers compost manure, there has been some confusion about how far RTF coverage extends, especially for farmers who: a) bring feedstocks used in compost production onto the farm, and b) sell or give away compost to others. The purpose of this article is to clarify what coverage a farmer can expect under RTF if he/she chooses to compost manure.
Biological treatment method
According to the Manure GAAMPs, a biological treatment system is designed to convert organic matter, such as feed, bedding, animal manure, and other agricultural by-products, to more stable end products. Composting is listed as a biological treatment method in the Manure GAAMPs. Therefore, compost production, as a biological treatment system for manure, is part
of a farm’s MMSP. Compost production practices referenced in the Manure GAAMPs are found in The Composting Handbook. Farms considering composting manure should add this handbook to their library.
Compost production scenarios
With regards to composting manure and the distribution of compost, four scenarios could occur on a farm. The feedstocks used to make the compost, scale of farm operation, composting method, and final utilization of the compost will determine whether the material and activities are covered under RTF or are regulated by the Michigan Department of Environment, Great Lakes, and Energy (EGLE) Waste and Hazardous Materials Division (WHMD) and/or Water Bureau for farms under a National Pollutant Discharge Elimination System (NPDES) permit. The scenarios are as follows:
In general, manure generated and composted on a farm (as a form of treatment) may be used on that same farm or taken off that farm for off-site utilization at another farm under RTF. Compost use and application should follow GAAMPs recommendations.
Manure generated on one farm and brought to a different farm for composting (as a form of treatment) may be used on the farm where it is composted under RTF, if managed according to GAAMPs. Any distribution of the composted manure from the farming operation will be considered “commercial composting” and subject to NREPA part 115 rules, as administered by EGLE WHMD.
Similarly, yard clippings (e.g., grass clippings, leaves, small brush, as defined by part 115) brought to a farm for composting (as a form of manure treatment) may be used as a soil amendment on that same farm under RTF, if managed according to GAAMPs. In most cases the farm will need to have and follow a Compost Operation Plan (COP) approved by the Michigan Department of Agriculture and Rural Development (MDARD). A COP includes a site plan, inventory of the amount of material(s) received, a description of how the materials will be composted, a description of storm water and runoff management practices, and utilization of the finished compost. For MDARD to make a GAAMPs determination under this scenario, the farm will need to:
- Submit a COP to MDARD.
- Allow MDARD to conduct an on-site inspection.
- Produce adequate records to document adherence to the COP and conformance to the Nutrient Utilization GAAMPs.
Yard waste, food waste, and other organic materials brought to a farm for composting (not as a form of manure treatment) and distributed from that farm in any form (raw yard waste, partially composted compost, or finished compost) is considered a commercial composting facility and is solely under EGLE jurisdiction. A farmer has no RTF coverage under this scenario.
RTF coverage extends to all farms that make compost for their own use, as long as it is managed according to GAAMPs. Anything beyond this designation is considered commercial composting and does not receive RTF coverage. These operations fall under the purview of EGLE. If a farm is used as a commercial composting site, permits may be obtained from EGLE. Contact your local Michigan State University Extension office for more information about on-farm compost production.
A version of this article was first published in the January 2009 Michigan Dairy Review by Charles Gould and Steve Mahoney.