Cover crops—organic mainstays—move into mainstream
By Jody Padgham, MOSES
Cereal rye and oilseed radish have been appearing in a growing number of fields around the country in the past few years. A standard practice for successful organic farmers, the use of cover crops now is being explored by many non-organic producers, especially as the NRCS has ramped up encouragement of this soil-enhancing practice.
Two meetings recently advanced the practice of cover crop use. In mid-February, the National Conference on Cover Crops and Soil Health convened in Omaha, Neb. Organized by Sustainable Agriculture Research and Education (SARE), the conference brought together over 300 representatives of agricultural industry, the farm community, academia, government, commodity and conservation organizations to discuss how to make American agriculture more sustainable by improving soil health. On-site participants were joined by 6,000 others meeting in local NRCS and Extension offices to engage in conversations on cover crops and soil health.
In mid-March, the Wisconsin Cover Crops Conference included over 100 attendees interested in the economic and soil health benefits of cover crops. This state conference was hosted by Michael Fields Ag Institute, NRCS, and UW-Extension, and sponsored by North Central SARE.
Dave Campbell of Lily Lake Organic Farm in northern Illinois attended the national conference where he saw many large-scale conventional farmers who were enthusiastic and engaged during the entire two-day event.
“In organics we’ve known about the benefits of cover crops for a long time—I’ve been using cover crops for the past 26 years,” Dave said. “I wish they would have joined us 20 years ago; although nonetheless, it’s rewarding to see how much emphasis NRCS is now putting into this invaluable practice. I applaud NRCS for their commitment to improving our soil health.” Dave is especially excited to see ramped-up support for cover crops as more funding and interest is being targeted toward cover crop research. He thought one of the most important aspects of the national conference came during the final sessions during which recommendations for changes in national policy were discussed.
Christine Mason, farm manager at Standard Process Inc. a 420-acre organic vegetable farm in Palmyra, Wis., had similar thoughts after speaking at the Wisconsin meeting. “I’d guess about 50% of the attendees were conventional growers,” Christine said. “Unlike organic farmers, diversity isn’t mandated—so they were there solely out of interest in improving the soil. This was very exciting.”
Christine and Dave are passionate about the value of cover crops on their farms. “Cover crops are the main source of fertility on our farm, but they have many, many other benefits,” Christine explained. Standard Process is a unique farm raising a diversity of vegetables that are processed into whole food supplements. “When we harvest a red beet, or any other vegetables we grow, we are taking those nutrients away from the soil. Cover crops are essential on our farm to replace the fertility we are removing.”
After many years of using cover crops on his 224-acre organic grain and hay farm, Dave knows what works well for soil fertility as well as weed control. A year ago last April he seeded red clover in with winter wheat. Shortly after the wheat was harvested, he clipped the clover cover crop during late July in order to encourage more growth which increases biomass content. The clover grew back again and will remain untouched until around the first week of May when it will then be moldboard plowed. Corn, hopefully, will then be planted later in May. Dave also likes to rotate his tillage practices, and, at times, will substitute spring moldboard plowing for late fall chisel plowing of clover fields prior to planting corn.
Although Dave knows what works, he still likes to experiment and refine some practices he has tried in the past. This year he is excited about some test plots on his farm where a mix of oilseed radish, buckwheat and oats were planted during mid-August of last year. All of these cover crops will winterkill, and so the ground will need only light tillage before corn is planted. This is especially helpful in years with cool and wet spring weather, which happens more often than not where he farms. Dave plans to compare corn yields between this three-crop mix versus the clover he traditionally uses. He will also be observing differences in weed pressure between these two systems.
“What I like about this mix,” he stated, “is that each cover crop provides a different function—the radish root provides deep rooting which aides in alleviating soil compaction at deeper levels such as the plow pan layer. Buckwheat provides some allelopathic weed suppressing effect on annual weeds that will compete with the corn crop, and oats will provide plenty of cover for winter and early spring erosion control. Oats are also great at scavenging excess nutrients such as nitrogen.”
Christine, too, is fond of what she calls “cocktail mixes.”
“You can make up your own mix,” she said. “Planting crops you can combine yourself is cost effective and makes mixes more affordable.” Her farm’s cover crop plantings on low lying soils change with the seasons. In spring, barley, oats and chickling vetch are planted. In summer, the mix includes barley, buckwheat and berseem clover. In fall, the mix typically includes barley and crimson clover. “These are all annuals, and so we won’t need much tillage,” she added. Spring- and summer-seeded cover crops will be rotovated while still green. Fall-seeded cover crops will die in the winter and require shallow incorporation the following spring.
“Why not grow your nitrogen instead of buying it?” Christine concluded. “Cover crops make our farm sustainable.”
Organic farmers can benefit from the increased interest, discussions and resources about the benefits and effective use of cover crops. All of the presentations from the National Conference on Cover Crops and Soil Health, including 10 videos of farmers successfully using cover crops, are available at www.sare.org/Events/National- Conference-on-Cover-Crops-and-Soil-Health. Dave also recommends the resources and activities provided by the Midwest Cover Crops Council at www.mccc.msu.edu.
Jody Padgham is the Financial Director for MOSES, and Associate Editor of the Organic Broadcaster.
From the May | June 2014 Issue