Corn roots secrete certain chemicals that affect the quality of the soil. In some fields, this effect increases yields of wheat planted subsequent to corn in the same soil by more than 4%.

Ryan Gibbs, Hopkinton, Iowa, no-tiller and owner of Gibbsfield Ag, shows how he makes compost extract for production agriculture fields. He says the extract, made by washing dry compost, applied as a liquid in furrow is the equivalent of using a few thousand pounds of dry compost per acre.