As farmers across the globe look to grow food more sustainably – with less water, fertilizer, pesticides and other environmental impacts – the use of cover crops is becoming more popular. These crops, which are often grasses or legumes, but also many other types of plants, are generally grown between the harvest and planting season of the land’s main cash crop, to reduce erosion, build soil fertility and control weeds, among other benefits. Their use has jumped in recent years. From 2012 to 2017, U.S. cover crops increased to 6.2 million hectares, an increase of 50 percent.
But the growth in cover cropping may soon hit a ceiling: planting millions of acres of cover crops will require huge extensions of land to produce cover crop seed. Between 3 and 6 percent of the 92 million acres of cropping land currently used for corn (maize) in the U.S. may be required to produce cover crop seed for that land area.
Researchers estimated that range based on 18 cover crops currently used on corn farmlands. Thestudywas published June 11 in Communications Biology, a Nature journal, by scientists at the University of Minnesota, University of Southern California, Saint Louis University, University of Hawaii, and the Alliance of Bioversity International and CIAT.