Cover Crops: Not Just Foul Weather Friends

Cover crops proved themselves foul weather friends during the Great Drought of 2012. A groundbreaking farmer survey conducted in the Upper Mississippi River watershed showed that during that year's brutal growing season keeping the soil covered with small grains and other plants helped fields preserve enough precious moisture to provide a yield bump of, in the case of corn, around 11 bushels per acre. Soybeans planted after cover crops enjoyed a yield advantage as well that year, according to the survey, which was conducted in states like Minnesota, Wisconsin, Iowa and the Dakotas, among others.

That's exciting, but let's face it: average U.S. corn and soybean yields took major hits in 2012 as a result of the mega-drought. Just about any alternative farming technique that could save even a semblance of moisture had a good chance of providing an advantage. What about in a more "normal" year?

The partial answer to that question emerged this week in Omaha when Rob Myers released a few preliminary results from a 2013 follow-up to that initial survey. During the first morning of the National Conference on Cover Crops and Soil Health, Myers reported that in 2013 corn planted after cover crops produced on average 10 more bushels per acre when compared to its non-cover cropped counterparts. Soybeans after cover crops also yielded well in 2013— a season full of challenges but a widespread mega-drought was not one of them.

When cover cropping starts to prove itself year-after-year in varying conditions, it builds the reputation of being a reliable farming technique. And that yield bump means that cover-cropped corn had a net return advantage of around $35 per acre, according to Myers, who is the regional director of Extension Programs for the USDA's North Central Sustainable Agriculture Research and Education (SARE) program. That's an important figure to keep in mind because the median cost of putting in a cover crop—paying for the seed and doing the planting—was around $37, according to the survey.

"That [$35] is close to the cost of seed and seeding, but maybe not enough to convince someone who is on the fence," Myers told the more than 300 farmers, scientists, conservation professionals and extension educators gathered in Omaha.

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Maybe not, but as subsequent presenters made clear during this two-day event, the other "extras" provided by cover cropping could go a long ways toward pushing more farmers over onto the cover cropping side of the divide.

For one thing, cover cropping's ability to build soil health can provide a significant amount of "free" fertility while breaking up pest cycles and reducing compaction. Each 1 percent of organic matter holds the equivalent of $700 in soil nutrients, according to Ohio State University's Extension Service.

During a conference panel discussion farmers from Iowa, Illinois, North Dakota and Ohio talked about how building soil with cover crops has helped them cut fertilizer and pesticide use—in some cases significantly.

"I have used no synthetic fertilizers since 2008," said North Dakota farmer Gabe Brown, who uses cover cropping as part of a diverse, integrated system that involves no-till and mob grazing.

Mob grazing of cover crops is another economic boost that was talked about at the conference.

"People say grazing is the fastest way to recover the cost of cover cropping," said Myers.

But those are just the on-farm economic benefits of cover cropping. The off-farm pluses are also starting to pile up. Iowa State University research presented at the conference showed cover crops cut nitrogen fertilizer runoff and soil erosion by half. The other "public" benefits are more wildlife habitat and sequestration of greenhouse gases.

Another potential economic plus that was mentioned more than once at today's conference has particularly significant implications given the recent passage of a new Farm Bill that is heavily reliant on crop insurance. Wouldn't soils made more resilient by cover cropping and other sustainable methods be less likely to produce the kinds of crop failures that result in big crop insurance payouts? Given the public's increasing investment in federally subsidized crop insurance, we may have more of an incentive than ever to see our soil taken care of.

And in the end, it will take public support (or pressure) if cover crops are to go beyond the 3 million acres or so Myers estimates they grew on in 2013. In fact, organizers of the conference—SARE, the Howard G. Buffett Foundation and the Soil and Water Conservation Society among others—have a goal of seeing 20 million acres of U.S. farmland covered in cover crops by 2020. That's an ambitious plan, one that will require significant buy-in by a whole lot of farmers who right now are really good at just growing one or two kinds of row crops for a few months out of the year.

And getting that buy-in means not only communicating the benefits of more life on the land to those who make a living off it, but everyone else as well, said Ray Archuleta, a conservation agronomist at the USDA's Natural Resources Conservation Service whose super-charged presentations about soil health would put a TV evangelist to shame.

"Folks, we have a whole society that is disconnected from the land," Archuleta said during a conference presentation while showing Dust Bowl-like images that had been photographed within the past 12 months. "How are we going to get covers if we don't understand why we need covers?"

Brian DeVore is the editor of the Land Stewardship Letter and the author of the recent article, "The Roots of Healthy Habitat."