Midwest farms are using more cover crops. Why that’s good news.

For years, agricultural experts have promoted the use of cover crops that are planted on fallow fields in an attempt to repair soil and slow erosion. But how many farmers have taken up the call and covered their cash-producing fields? Given the size of the nation’s Midwestern agricultural belt, that question is almost impossible to solve on the ground. So researchers turned to satellites and discovered the practice is on the rise.

In a study in the journal Geophysical Research Letters, researchers write that cover crops have “significantly” increased throughout the Midwest.

Cover crops are used in place of crops intended for sale or animal forage. Farmers most commonly use rye or winter wheat for cover. Instead of being bare and exposed to the elements and erosion, these fields resist erosion. As the crop grows and decomposes, its nutrients are absorbed by the soil. And according to the U.S. Department of Agriculture, the crops can dry out wet fields before planting and even increase future crop yields.