Dan Forgey is a master of mixology. His signature cocktails are blends of grasses, legumes and brassicas. He is agronomy manager for Cronin Farms, an 8,500-acre crop and cow-calf operation in central South Dakota. He grows eight cash crops – including corn, soybeans and wheat – and juggles an equal number of cover crops, which include field peas, oats, turnips, radishes, canola and flax.

Forgey has grown cover crops since 2006 on the sprawling no-till farm near Gettysburg, SD. His cocktails manufacture, catch and store nutrients for the corn crop, stop erosion, smother weeds, preserve soil moisture and supplement grazing.

Cover crops are nothing new. Only a couple of generations ago, it was routine to seed sweet clover with small grains for nitrogen (N) fixation, livestock feed and postharvest weed competition, says Dwayne Beck, director of South Dakota State University’s Dakota Lakes Research Farm at Pierre.

Beck has preached cover crops for 20 years. The practice dropped off with the rise of cheap commercial fertilizers and tillage. Now, with higher fertilizer prices and more no-till production, growers like Forgey are rediscovering the advantages of cover crops, Beck says – especially cover-crop mixes, which allow you to achieve “several goals simultaneously.”

Cover crops offera wide range of environmental and agronomic benefits, says Paul Jasa, University of Nebraska Extension engineer. They can prevent wind and water erosion on land that would otherwise be bare, reduce runoff and N leaching, build soil structure, break up compaction, fix N, recycle nutrients, feed beneficial soil organisms and supply extra forage.

Cover crops can preserve moisture in dry areas, or use up excess moisture in wet areas, Jasa says. You can also manage residue with proper cover-crop selection: “You can either get rid of excess residue in a hurry, or build up residue.”

In Nebraska, cover crops are becoming popular in livestock areas, where growers are planting triticale, cereal rye and wheat right after chopping corn silage “to give bare soil cover and rest pastures,” Jasa says.

Seed-corn growers, who harvest early, are planting turnips and radishes into standing stalks to provide grazing and speed up residue breakdown. And with wheat production on the rise, more growers are drilling cover-crop mixtures into wheat stubble in late summer to build soil organic matter and suppress weeds, Jasa says.

Dan Forgey’s primary aimin using cover crops“is to help build soil health.” He converted Cronin Farms to no-till 19 years ago. Since then, average organic matter levels have risen from 2.5% to about 4%. His strategy is to “build organic matter and then let our organic matter supply our nitrogen” through mineralization. Cover crops, he says, are “the next step in no-till.”

Forgey plants about 700 acres of cover crops each season, seeding into winter wheat stubble with a no-till drill in mid-August. In 2010 he planted a mixture of canola, field peas, oats, radishes and flax, and injected 25 lbs./acre of N as urea.

Each plant contributes something the soil needs, Forgey says.

“Canola has a good taproot, and it’s a bushy plant with lots of carbon and biomass. Field peas fix N. Radish has a deep taproot that breaks up compaction and improves water infiltration,” he says.

Flax and oats have large, fibrous root systems that improve soil structure and feed soil microorganisms. “Flax stands all winter,” trapping snow and stopping erosion, and oats do a great job of scavenging N and recycling phosphorus (P),” he says.

Cover-crop mixes like Forgey’s usually perform better than single crops, Beck says. “Mixtures add more diversity, grow at different times, better compete with weeds, optimize nutrient cycling” and make more efficient use of moisture.