DEVILS LAKE, N.D. — When done right, composting manure and livestock is an environmentally sound way to dispose of animals and their waste, according to Mary Keena, North Dakota State University Extension livestock environmental specialist.
Composting livestock manure has benefits including killing pathogens, reducing weed seeds and killing parasites, Keena told farmers at the Lake Region Extension Roundup held in Devils Lake on Jan. 3-4, 2024. Meanwhile, composting dead animals is a better option than other disposal methods, such as burning, said Keena, who works at the NDSU Carrington Research Extension Center.
When composting, it’s important to select a compost site where leaching won’t contaminate groundwater or where the leachate can run off into surface water, Keena said. For example, sandy soils have rapid permeability, which allows leaching while loamy or clay soils have slower permeability, which helps to keep nitrates in the soil profile.
The site where the manure stockpile will be composted must not be located in a gravel pit or another place where there has been an excavation, along streams or lakes, within a floodplain or near a sinkhole, or within a certain distance of a private water supply well, a public supply well or watertight casing, Keena said.
Once the manure compost site has been selected, management of the compost is key so it won’t spread weed seeds and will be an effective fertilizer.
If one weed seed that cattle have eaten escapes the heat in composting and then is spread onto a crop field, the plant from the seed has potential to annually produce as many as 1 million weed seeds in a year. Even if the weed plant competes with a crop, it can still produce 100,000 weed seeds annually, according to research from Joe Ikely, NDSU Extension weed specialist.
Meanwhile, manure has potential to encourage growth of weed seeds that already are in the soil.
“Heat is a huge part of composting,” Keena said.
Manure that is composted typically is piled in windrows that can be turned over by mechanical equipment, such as payloaders, skidsteers, front-end loaders. Compost turners or pitchforks can be used for small piles.
Water management is key to composting because 40% to 65% of the pore space in composting materials should have water. A simple way to determine the amount of water in the pile is to take a handful of compost and squeeze it. If water drips out, it’s too wet. However, if it feels like a wet rag that has been wrung out, it has enough moisture, Keena said.
The optimal time to turn the piles, which can be determined by using a probe-type thermometer, is when the internal temperature drops below 120 degrees F. The manure should be composted after five or six turns. The process can take as little as six weeks or as many as six months, Keena said.
Once the manure is composted, it can be piled so it can “cure,” which takes a month or longer.
When the compost has cured, livestock producers should take samples of the pile at various spots and mix them, then send them to a laboratory for analysis or place them in cold storage until they can be sent to the laboratory.
The compost should be applied with a calibrated spreader to ensure that the proper amount of nutrients are applied and to reduce the chances of polluting.
Composting dead livestock, instead of burying or burning animals, is an option for farmers and ranchers. Similar to manure composting, it must be done correctly so it does not cause contamination of the groundwater.
The four easy steps for dead livestock composting are, according to Keena:
- After choosing a suitable site, place 2 feet of carbon base material in a pile or long row, depending on the number of animals to be composted.
- Place the dead livestock on top of the base. Make sure that there is at least 1 foot of base material between the perimeter of the animal and the edge of the base.
- Cover the dead animal with 8 to 10 inches of bulking material.
- Cover the whole pile or long row with 2 feet of cover material such as straw.
Keep in mind
Small-sized dead livestock can be layered on top of each other when there is bulking between layers.
Ruminant animals should have their rumens punctured to prevent exploding.
The pile should have sufficient cover material to keep bulking material and dead livestock covered and be turned every six months from early spring to late fall. The pile can be turned every two months from early spring to late fall to speed up composting.
Existing compost can be used to cover new piles or long rows.
The compost should be sorted through to remove any remaining bones — which could puncture equipment tires — before it is spread on fields.
Ann is a journalism veteran with nearly 40 years of reporting and editing experiences on a variety of topics including agriculture and business. Story ideas or questions can be sent to Ann by email at: firstname.lastname@example.org or phone at: 218-779-8093.
Powered by WPeMatico
Go to Source