(Radio Iowa) – As Iowa farmers start putting together the finances for the next growing season, they’re again considering liquid manure rather than commercial fertilizer for cropland. Nitrogen and phosphorous are typically applied to corn and soybean fields, but a global shortage of commercial fertilizer has caused prices to spike. Iowa State University Extension agricultural engineer Kris Kohl can liquid manure from livestock operations can be a cheaper alternative.

“Typically a person that’s buying manure is going to get it for probably 80 or 90% of what the equivalent fertilizer is, so that’s a savings,” he says. “Oftentimes they’ll get the micro nutrients, the sulfur and zinc, thrown in for free.” I-S-U Extension will host a workshop on August 1st in Storm Lake for those who have manure to sell and those who are looking to buy it. Anyone buying manure in bulk for the first time needs to collect soil samples from farm fields and file a manure management plan with the Iowa Department of Natural Resources.

“Our research at Iowa State shows there’s a slight advantage to using manure over commercial fertilizers,” Kohl says. In a typical year, I-S-U experts estimate 14 BILLION gallons of manure are spread on Iowa fields. Transporting liquid manure can be costly, though, and environmentalists are raising concerns about drainage from fields into rivers and lakes.