Like fashion from your favorite decade, cover crops have come full circle and are once again en vogue.

Just two short generations ago, cover crops were standard procedure on family farms. Life was different then, though, as small family farms had a variety of animals and planted a diverse selection of crops to support themselves and their livestock.

There was no synthetic fertilizer. Farmers had to come up with their own by growing legumes or spreading manure.

“Producers would grow red clover to provide nitrogen for their corn crops. It was part of a very complete cropping rotation,” says Dale Mutch, Michigan State University cover crop and IPM extension specialist.

But the role of cover crops diminished as farming systems changed. As the Industrial Revolution evolved in the U.S., farm kids headed off to work in the city.

Farm consolidation took hold, and herbicide development and larger machinery allowed for ever-expanding farms. Many farms also became less diverse in their rotations.

The final nail in the coffin was the creation of synthetic fertilizer, which made it relatively easy to buy and apply the nutrients crops needed.

“Fertilizer and herbicides were simply more cost-effective at the time,” says Steve Groff, Holtwood, Pa., no-tiller and cover-crop innovator. “And with heavy use starting in the 1940s through the 1980s, we gradually lost the biological component in our soils to synthetic fertilizer use.”

The use of nitrogen, phosphate and potash in the U.S. reached 7.5 million nutrient tons in 1960 and climbed to 23.7…