From the feedlot to the dairy, and every livestock enterprise in between, figuring out some way to handle manure is a stinky task no one likes to take on. But with a little bit of work and ingenuity, farmers can turn that stink into opportunity for their farms.

A team of researchers at the USDA Economic Research Service found earlier this year that there is an opportunity for farmers to increase their use of manure fertilizer. According to the team’s study “Increasing the Value of Animal Manure for Farmers,” manure was applied to just 8% of the 237.7 million acres planted in 2020 to our nation’s top seven field crops. Of those acres of applied manure, 79% were planted to corn, and 26% were planted to hay or grass.

But there are a few challenges to replacing commercial fertilizers with manure.

To start, manure’s high water content — up to 90% of its total weight — means that has a low nutrient-value-to-mass ratio. So, farmers may have to transport and apply more loads, adding to their costs, according to the report.

Manure is a great source of nitrogen, but it also comes with more phosphorus than a plant needs, which could run off and pollute waters. And because of variation in feedstocks, results can vary if you don’t test before you apply.

The study also found that large farm operators are more likely to use commercial fertilizers over manure for their precise application and ease of use. Meanwhile, smaller-scale farmers are generally more likely to use manure because they may have integrated livestock in their operations.

Composting

The USDA report shows that 78% of applied manure comes from diversified farms that raise crops and livestock, while 14% is purchased from other farmers and 8% is obtained for free. When you consider the recent spikes in commercial fertilizer costs, many farmers are looking to manure as an alternative. There’s value in the pile, you might say.

One way to capture that value of manure is to compost it. Composting uses bacteria to stabilize the manure’s organic matter and nutrients, reduce its volume and reduce pathogens. The National Center for Appropriate Technology, Butte, Mont., offers a tip sheet for farmers interested in composting their manure.

Here are some of the NCAT tips:

Value streams

Manure isn’t just a great source of nutrients for plants, though. The USDA ERS report shares that farmers could also find value from other revenue streams for their livestock manure in the developing carbon economy.

Anaerobic digesters are already producing renewable energy from the methane from manure that farmers can use on their farms. The high cost of the technology and the maintenance required of digesters, though, has limited early adoption by farmers. But, as carbon credit trading and incentive programs grow in popularity, the USDA researchers predict that it will increase demand for them.

Even the byproducts of the anaerobic digesters — the manure fibers — can have a second life as biodegradable containers for horticultural plants.

Read the full report.

USDA Economic Research Service contributed to this article.