Follow do’s and don’ts for livestock disposal
You can burn, bury or compost carcasses, says Chris Augustin, area nutrient management specialist at North Dakota State University’s Carrington Research Extension Center.
But burning and burying have drawbacks, he says.
When burying dead animals, you need to avoid areas with sandy soils and shallow water tables. The site should be nearly level to moderately sloping and at least 200 feet away from surface water. The bottom of the disposal pit should be at least 4 feet above the water table and underlain with loamy, silty, clay soils. Carcasses should be covered by 4 feet of soil.
Also, do not locate the burial pit near residences, wells, shallow aquifers or areas that may be flooded, and avoid pipelines, utility easements and historically significant sites.
Burning can be difficult because the law requires use of organic fuels, such as wood, which can make creating enough heat to effectively combust a carcass difficult. Also, the state Department of Health must grant an open-burning variance prior to the burn.
• Composting may be the best way to dispose of carcasses.
• Composting is simple, but it needs to be managed properly.
• The carcass needs to be covered with wood or straw and turned regularly.
Composting may be best
Composting may be the best solution for handling dead animals because it is effective and cost-efficient, Augustin says. Composting carcasses is a simple process that, through time, changes the animal to a soil-like product.
However, the composting pile needs to be managed properly. You need a bulking material high in carbon, such as wood chips or straw. Place about 2 feet of the bulking material in an area that drains well, but where runoff will not reach waters, such as rivers, lakes or streams. Place the carcass on the bulking material and add another 2 feet of bulking material on top of the carcass. The animal will undergo thermophylic decomposition.
During this period, temperatures in the pile will range from 120 to 160 degrees F as bacteria feed on the animal and bulking material. Temperatures should be monitored with a probe-type thermometer.
The pile also requires adequate moisture and oxygen. The pile should have about 60% of the pores filled with water and the remaining pores filled with air. The bulking material helps the pile maintain oxygen.
After about 90 days, the pile should be turned with a front-end loader to incorporate more oxygen. More bulking material and water may need to be added at this time. You should continue to monitor the pile’s temperature. When the temperature falls below 120 degrees F, the pile should be turned again. After about six months, and three to five turns, the carcass should be entirely composted.
The benefits of composting include reducing the amount of animal carcasses, destroying pathogens and eliminating odor. Also, pests tend to stay away from the pile.
“The finished product is an odor-free, soil-like fertilizer that adds a little value to a dead animal,” Augustin says.
Source: NDSU Extension Communications
STEP 1: A calf carcass is covered with straw. Water is added to begin the composting.
STEP 2: The compost pile is turned to maintain oxygen and moisture levels.
STEP 3: After about six months, all that remains of the carcass are some bones.
All Photos BY: Chris Augustin, NDSU
This article published in the April, 2010 edition of DAKOTA FARMER.
All rights reserved. Copyright Farm Progress Cos. 2010.