Biochar Improves Manure Management

Biochar offers an eco-friendly solution to manage farm animal manure by capturing excess nutrients, reducing odors, and diminishing greenhouse gas emissions. Its use has proven benefits in livestock operations, resulting in better soil health, improved animal well-being, and potential cost savings. With testimonials from farmers and research support, biochar presents a compelling case for sustainable farming, beneficial both for the environment and the economy.

US Biochar Initiative
Nebraska Forest Service
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Biochar and Farm Manure: A Winning Combination for Sustainability and Profit

Farm animal manure provides essential nutrients to enhance soil health. But there's a downside: excess manure can lead to nutrient overload and odors that negatively impact the environment and communities. Enter biochar—a natural solution to these challenges.

What Does Biochar Do?

1. Manages Nutrients: Biochar, when mixed with manure, captures excess nutrients. This results in high-quality, nutrient-rich compost that can be re-used on farms, saving on fertilizer costs.
2. Odor Control: Livestock operations often battle with the unpleasant smell of manure. Biochar acts as a deodorizer, reducing those unwanted odors and improving air quality for both animals and humans.
3. Environmental Impact: Excess nutrients can harm our water bodies. But with biochar's ability to bind nutrients, especially from liquid manure, we see less contamination in water sources. Plus, biochar can reduce greenhouse gases by a staggering 79%!

Farmers Speak: Real-life Success Stories

  • Poultry: Farms using biochar in chicken houses noticed a significant drop in ammonia buildup. This change not only improves the health of the birds but also protects nearby water sources from nitrogen runoff.
  • Cattle: Oregon rancher Troy Michaels found that by integrating biochar into his soil treatment, he reduced soil acidity without the high costs of traditional methods. Moreover, the compost produced was rich in nitrogen.
  • Beef Cattle: Research at the University of Nebraska-Lincoln showed that adding biochar to feedlot surfaces enhanced manure's nutrient quality. Furthermore, cattle experienced better weight gains, and pens dried faster after rains.

The Bigger Picture

For the construction industry, biochar's ability to control odors and manage nutrients presents an opportunity. By converting waste into a valuable resource, construction sites can benefit from an environmentally-friendly soil amendment. This isn't just good for the planet—it's a cost-effective solution.

For policymakers, supporting biochar use can deliver tangible economic and environmental results. Programs that encourage biochar production, like those offered by the USDA, not only boost local economies but also pave the way for sustainable farming.

Farmers, construction workers, and policymakers alike should consider biochar as an innovative tool for sustainability, profitability, and environmental protection.

Farm animal manure can be a useful amendment to build soil organic matter and provide important nutrients for crops. However, too much manure could be problematic, leading to excess nutrients and odors. Agricultural non-point nutrient pollution may contribute to the contamination of water bodies.1 Biochar offers a solution to enhance nutrient management and reduce the odors emanating from manure. When integrated into the solid fraction of manure, biochar can significantly enhance the capture of surplus nutrients and mitigate odors. In livestock operations, biochar proves beneficial for managing the smell of manure and controlling flies. It can also bind nutrients from the liquid portion of the manure. The process of upcycling nutrients from farms using biochar results in a richer, more nutrient-dense manure compost product that can be reintroduced to farm fields. Not only does this reduce manure odors, enhancing air quality and health for animals, but it also presents various benefits. Using biochar to manage manure creates a nutrient-rich soil amendment, reduces odors, improves animal health, controls nitrogen (N) and phosphorous (P) in runoff, stores carbon in the ground as a soil amendment, and can reduce greenhouse gases by as much as 79%.

Various benefits come from using biochar to manage manure:
• Creates a nutrient rich soil amendment
• Reduces odors4
• Improves animal health5
• Controls nitrogen (N) and phosphorous (P) in runoff
• Stores carbon in ground as soil amendment
• Reduces greenhouse gases by as much as 79%6

Economic benefits

Given that most animal agricultural operations have excess nutrients, using biochar to capture and store nutrients as a compost-fertilizer could be a source of new revenue for farmers, replacing petroleum-based fertilizers. From 2016 to 2018, Kelpie Wilson conducted a series of on-farm biochar trials in Oregon while working with the USDA. Here’s what farmers said:

Biochar in feed

Troy Michaels of Michaels Ranch in Days Creek, OR, noted that adding biochar directly to the barn produced composted manure with ten times the nitrate content of plain manure. "It is definitely worthwhile and more effective to add the biochar to the barn floor and have the animals mix and deposit on it. The increase in nitrate should be really beneficial."

"We were very impressed by the odor-reducing power of biochar. It has significantly improved our barns. When you dig into the floor, it appears to be composting very well. Instead of a heap of wasted hay and alfalfa, it’s now nice compost," said Suzanne Willow of Willow-Witt Farm in Ashland, OR.

Manure disposal entails unnecessary expenses and time for farmers. By introducing biochar, manure can be converted into a product that is usable on the farm or can be sold as a fertilizer.

Environmental benefits

Farms of all types are facing challenges to reduce nutrient runoff in order to protect waterways. Farmers are also interested in reducing manure odors both during stockpiling and field application. Using biochar to manage manure addresses these issues.

Researchers and farmers are exploring various ways to utilize biochar in animal husbandry. Some applications under discussion include:

  • Adding it to feed, a common practice in Europe and Japan.
  • Incorporating biochar in bedding.
  • Investigating biochar's impact on milk production.
  • Capturing wastewater phosphorous.

Case History: Poultry

CHALLENGE/OPPORTUNITY: The accumulation of ammonia in chicken houses creates an unhealthy environment for the animals and can lead to water pollution.

SOLUTION/APPROACH: Focused on producing engineered renewable carbon products, enviraPAC offers pre- and post-stage biochar to the poultry industry. In the pre-treatment stage, the aim is to control ammonia buildup in chicken houses that can accommodate up to 25,000 birds each. Biochar interrupts ammonia formation, prevents crust formation in the litter, and enhances bird health. When litter is removed from the house, it is often stacked, and rain can wash out nitrogen-containing material from the piles, becoming a major water pollution source. Mixing biochar into used litter absorbs nitrogen, thus reducing nutrient runoff, and produces an enriched compost product with a pH range of 7 to 8, making it a superior fertilizer.

RESULTS: enviraPAC biochar maintains standardized and consistent quality, ensuring reliable outcomes. A recent University of California Merced study demonstrated biochar's ability to reduce nitrogen runoff. Adding one ton of biochar per 15 tons of manure (about 6% biochar on a wet basis) or 0.9 tons of biochar per 3.37 dry tons of manure (almost 20% biochar on a dry basis) resulted in a 79% reduction in methane emissions. This addition also created nitrogen-rich compost and reduced greenhouse gas emissions.

Case History: Cattle

CHALLENGE/OPPORTUNITY: Commercial rancher Troy Michaels raises grass-fed beef and lamb on his 756-acre Oregon family farm. Over time, soils become more acidic, and using lime to adjust pH is costly.

SOLUTION/APPROACH: Michaels evaluated high-carbon boiler ash biochar from a nearby sawmill with a pH of 8.4 and a calcium carbonate equivalent exceeding 25% as a liming agent. Four options were assessed: pure biochar, pure manure, a biochar-manure mixture, and no treatment.

RESULTS: Preliminary data suggests that the biochar and manure mix, after the composting process, contained more nitrogen than the manure pile alone, indicating reduced nitrogen loss during decomposition. Michaels continues to use biochar due to its positive results. Similar outcomes were observed in other biochar-manure combinations. A 2022 University of Iowa study indicated that biochar-manure mixtures can provide substantial levels of nutrients, reducing costs of inorganic N and P for crop fertilization.

Case History: Beef Cattle Manure Management

CHALLENGE/OPPORTUNITY: Beef feedlot finishing diets in the U.S. contain high proportions of concentrate (grains) along with byproducts, crop residues, and forages rich in N, P, and soluble salts. Less than 15% of N and P are retained by animals, leading to their excretion in manure. Applying biochar to feedlot pen surfaces is a proposed method to enhance manure nutrient capture.

SOLUTION/APPROACH: Dr. Andrea Watson and colleagues at the University of Nebraska-Lincoln studied the effects of biochar addition to feedlot pen surfaces on manure nutrient capture. The biochar amendment was found to increase manure N content as a percent of manure dry matter, though not statistically significantly.

RESULTS: Adding biochar (25 to 31 kilograms per animal) significantly increased "Average Daily Weight Gain" and final body weight in a summer experiment. Faster drying of biochar-amended pens following rain events reduced mud formation. Similar effects on moisture content were reported in another study.

In conclusion, research and practical applications demonstrate that combining biochar with manure can yield significant economic, social, and environmental benefits. Biochar efficiently captures nutrients from farm manure and runoff, saving farmers on fertilizer costs and reducing greenhouse gas emissions. To promote biochar use on farms, the USDA Natural Resource Conservation Service (NRCS) offers incentive programs for biochar production. The 2022 Inflation Reduction Act also allocates additional funding for climate-smart agriculture practices at the farm and ranch scales.

Helpful Resources

  • To promote the wider use of biochar at the farm scale, the USDA Natural Resource Conservation Service (NRCS) has new incentive programs to cost share the production of biochar. The program is called the Code 336 soil carbon amendment program.
  • The US Biochar Initiative has a helpful video introducing the USDA NRCS program.
  • The 2022 Inflation Reduction Act provides an additional $19.5 billion over five years for climate smart agriculture. The new funds are designed to generate climate mitigation benefits at the farm and ranch scales, expand access to financial and technical assistance for producers to advance conservation on their farm, ranch, or forest land through practices like cover cropping, conservation tillage, wetland restoration, prescribed grazing, nutrient management, tree planting and more.

Reference Guide

1. Sampat A.M., Hicks A., Ruiz-Mercado G.J., and Zavala VM. 2021. Valuing economic impact reductions of nutrient pollution from livestock waste. *Resources, Conservation, and Recycling.* (

2. Toth, J.D. and Dou, Z. 2016. Use and Impact of Biochar and Charcoal in Animal Production Systems. In *Agricultural and Environmental Applications of Biochar: Advances and Barriers* (eds M. Guo, Z. He and S.M. Uchimiya). (

3. Wilson, K. 2018. On-Farm Production and Use of Biochar for Composting with Manure. (

4. Maurer, D., Koziel, J., Kalus, K., Andersen, D., & Opalinski, S. 2017. Pilot-scale testing of non-activated biochar for swine manure treatment and mitigation of ammonia, hydrogen sulfide, odorous volatile organic compounds (VOCs), and greenhouse gas emissions. *Sustainability*, 9(6), 929–946. (

5. Gerlach, A., & Schmidt, H. P. 2012. The use of biochar in cattle farming. *Ithaka Journal*, 2012, 281–285. (

6. Harrison B.P., Gao S, Gonzales M, Thao T, Bischak E, Ghezzehei TA, Berhe AA, Diaz G, and Ryals R.A. 2022. Dairy Manure Co-composting with Wood Biochar Plays a Critical Role in Meeting Global Methane Goals. *Environmental Science & Technology.* Aug 2;56(15):10987-10996. (

7. Case study of Troy Michaels ranch. 2021. (

8. Banik C., Bakshi S., Andersen D. S., Laird D. A., Smith R.G., and Brown, R. C. 2022. The role of biochar and zeolite in enhancing nitrogen and phosphorus recovery: A sustainable manure management technology. *Chemical Engineering Journal* 456, 141003. (

9. Sperber J.L., Erickson G.E., Watson A.K. 2022. Evaluation of the effects of wood-sourced biochar as a feedlot pen surface amendment on manure nutrient capture. *Translational Animal Science*. Sep 10 6(4). (

10. Maharjan, B., and K. Wilke. 2021. Using coal char from sugar production in cattle manure management. *Neb. 2021 Beef Cattle Rep.* 95–98. (

This presentation was partially funded by the National Fish and Wildlife Foundation Innovative Nutrient and Sediment Reduction Grant Program.

Disclaimer: The views and conclusions contained in this video are those of the authors and should not be interpreted as representing the opinions or policies of the I.S. Government or the National Fish and Wildlife Foundation and its funding sources. Mention of trade names or commercial products does not constitute their endorsement by the U.S. Government, or the National Fish and Wildlife Foundations or its funding sources.

Statement: This material is based on work supported by the U.S. Environmental Protection Agency (Assistance Agreement No. CB96358201) and the National Fish and Wildlife Foundation’s Chesapeake Bay Stewardship Fund, which promotes community-based efforts to develop conservation strategies to protect and restore the diverse natural resources of the Chesapeake Bay.