Using manure to replace nitrogen fertilizers requires a trial-and-error approach, but it can be part of growing healthy crops, an organic apple grower says.
Jim Koan of Al-Mar Orchards in Flushing, Michigan, has used manure from local sources for a decade. As nitrogen costs climb higher, he believes the practice may be useful for orchardists trying to contain input costs.
Over the years, he’s changed his application and manure sources. In the early years, manure was spread throughout the whole orchard. He found, however, that he wasn’t getting enough manure under the trees where it was needed.
Recently, he began banding material under the drip line and incorporating it into the soil to speed up the work of the microorganisms.
“You have to teach yourself what works best,” Koan said. “It’s a trial-and-error approach.”
He splits applications of manure between spring and fall, watching tree growth closely. Before, he used about 1,000 pounds per acre of dried chicken manure each year. Lately, he has switched to using sawdust bedding from horse stalls.
Koan prefers the sawdust bedding as it is easy to spread, has high nitrogen content, and isn’t as “hot” as chicken manure.
Through practice, he has fine-tuned his applications. He spreads sawdust one-quarter inch thick, using an adapted row mulcher to place it over the soil. Koan then uses a disk used for weeding with spider-like fingers to incorporate it into the top of the soil. He can spread 30 to 40 tons per day.
He has not seen increased weeds from banding on the side of the tree.
“You use less fertilizer this way by tilling it into the top of the soil,” Koan said. “I’m growing my own nitrogen from the grass that’s there and is incorporated into the soil.”