Glen Arnold

“We have to give a lot of thought to how manure is applied,” said Glen Arnold, with Ohio State University Extension. “Our product is very visible.” He referred to the ‘4 Rs’ of manure application — right nutrient, right place, right time, and right amount — during his presentation at the North American Manure Expo held in Arlington, Wis.

One of the challenges with manure application is timing, due to both weather and growing seasons. “We need to make more days available for manure application,” Arnold stated.

One opportunity is to apply manure to growing crops. This practice is not widely done for fear of damaging the plants or compacting the soil, but application at this point can boost yield, reduce nutrient loss, and extend the window of manure delivery.

To accomplish this, Arnold and one of his colleagues, Sam Custer, helped design a metal tractor attachment that receives manure pumped from a storage tank. The manure travels through a toolbar and is injected 3 to 5 inches into the soil between the rows of growing corn. The manure is then covered with soil.

This tool came after about five years of research by Arnold. In one field trial, using the sidedress toolbar yielded 13 more bushels per acre of corn while using about $80 an acre less of synthetic fertilizer.

The sidedress toolbar can also be used on soybean and wheat.

Arnold pointed to the following reasons why sidedressing manure on growing crops may be a useful option for farms:

1. The tool could allow for application on smaller fields or organic ones where synthetic application cannot be applied.
2. This process is more forgiving to soils and causes less compaction.
3. Corn can be taller when manure is applied this way.
4. Efficiency is improved if manure is delivered to the edge of the field.

Finding ways to utilize more manure as a fertilizer is important to Arnold. “A lot of nitrogen is in manure. We are basically giving it away if we don’t try to capture it,” he said.

More information can be found at go.osu.edu/manureapplicator.