While the U.S. Department of Agriculture (USDA) reports a 40 percent decline in U.S. cropland soil erosion rates from 1982 to 2007, recent trends appear to challenge this progress. Record prices for corn and soybeans have diverted acres out of conservation programs and encouraged intensive production on a wide scale. Tree lines are cleared and wet areas drained, turning 120-acre farms into 120-acre fields. Innovations in tillage equipment, with supposed conservation intentions, appear to be encouraging more tillage and leaving less crop residue. Climatological data show changes in precipitation trends with more extreme rainfall events, apparently associated with climate change. In my 30-year career, serious gully erosion has never been more evident in several parts of Wisconsin. Nutrient runoff from farm fields in the Mississippi basin continues to be a major cause of hypoxia in the Gulf of Mexico.
Farms of all sizes and business organization have the ability to implement conservation practices. In my observation, family farms are uniquely suited to soil and water conservation. They can do so by employing crop and livestock production practices that focus on environmental quality as well as efficiency of production. Family-sized farms can recognize there is a competitive edge in practicing good stewardship, and may have a better ability than the largest farms to utilize ecologically based practices such as diverse crop rotations and integration of crop and livestock production. They often are more able and willing to implement and maintain field-based soil and water conservation structures such as grassed waterways or contour strips and terraces, and to develop and genuinely implement certified nutrient management and soil conservation plans. Due to their modest scale and greater hands-on management, they are often better able to match farming practices to the potentials and limitations of the landscape on which they farm. Family farms often recognize that by utilizing practices that build or improve the soil’s productivity, rather than exploiting or abusing it, profitability will be enhanced.
Another conservation practice gaining interest that fits nicely with intensively managed family-sized farms is the use of cover crops. Cover crops are planted to grow and cover the soil between harvest and planting of the primary cash and feed crops a given farm normally grows. Cover crops cover and protect the soil from erosion and prevent nutrient runoff during otherwise fallow or open ground periods. Other objectives for using cover crops include building soil organic matter and increasing biological diversity for soil conditioning and soil health; holding onto and recycling nutrients in the root zone, thus reducing leaching losses; adding nitrogen fertility if the cover crop is a legume species; suppression of weeds that would otherwise grow; possible crop disease suppression; and providing a source of supplemental forage for harvest or grazing if needed.
One example that can be used in the upper Midwestern states is frost-seeding medium red clover into winter wheat. Winter wheat is planted in the fall. Early the following spring, red clover seed can be broadcast into the small wheat crop while freezing and thawing causes cracks on the soil surface. The clover seedlings get started but don’t take off until the wheat is harvested in mid-July. Rather than having a weedy fallow period following wheat harvest, the clover can grow, suppress weed growth and biologically fix a stable source of nitrogen available for the following year’s corn crop. The clover can also be a source of hay for livestock feed if weather conditions allow a September harvest. Alternatively, annual species such as forage radishes, oats, barley or field peas will grow rapidly when planted in late summer to provide a cover crop following harvest of wheat or short-season vegetable crops.
Another example becoming popular in the dairy state is planting winter cereal rye following harvest of corn as silage. Corn silage leaves almost no crop residue remaining on the soil surface and it is a popular place for manure to be applied. Cereal rye can grow rapidly in early fall, establishing some soil cover to protect soil and hold nutrients against rainfall and snowmelt fall through spring.
To be economically beneficial, the cover crop species must be one for which affordable seed is readily available and seeding methods should be low-cost. Since they are generally planted for growth during sub-optimal times, and often with less precise planting methods, there are establishment risks. If not managed correctly, some cover crops can become weeds or hosts for insects or diseases themselves. A farmer needs to pay attention to soil-applied herbicide residues (from previous crops) and required planting intervals when planting a cover crop and/or using it for feed. There are sometimes issues associated with federal crop insurance products where use of a cover crop affects insurability of the primary, insured crop. In other words, there are economic risks and learning curves to successful adoption.
National Conference on Cover Crops and Soil Health
Fortunately, there are growing sources of information and expanding research programs to learn how to use and measure the costs and benefits associated with cover cropping practices. A National Conference on Cover Crops and Soil Health will take place this coming Tuesday and Wednesday, Feb. 18 and 19 in Omaha, Neb., where 300 invited researchers, educators, agribusiness professionals and farmers will come together to discuss obstacles to and opportunities for adoption of cover crops on U.S. farms.
The conference, sponsored by the Howard G. Buffet Foundation and the USDA Sustainable Agriculture Research and Education (SARE) program, will offer a free live broadcast and local forums to some 200 sites across the United States on Feb. 18. Find a forum location near you. The forums are open to anyone who would like to hear about and discuss the prospects for cover crops and soil health improvements on American farms and ranches. The broadcast will begin at 9:00 a.m. CST for participants from the Eastern, Central and Mountain regions of the United States. The broadcast will be re-streamed at 10:00 a.m. PST for participants in the Pacific region or further west. Attendees are encouraged to RSVP and arrive 30 to 45 minutes ahead of time for check-in and introductions. There is no cost to participate, but please contact the site you plan to attend to register and confirm both the location and other program details. Providing an RSVP will help host locations make adequate accommodations. Each forum will feature a live-streamed video broadcast of the opening sessions. Following the broadcast, discuss with fellow forum participants how cover cropping can build soil health, improve yields, curb erosion, manage pests and build resilience into your farming system.
The broadcast will feature:
- Howard G. Buffett, Howard G. Buffett Foundation
- Jason Weller, USDA-National Resources Conservation Service Chief
- Ray Gaesser, American Soybean Association president
- A panel of expert producer-conservationists:
- Dave Brandt (Ohio)
- Gabe Brown (N.D.)
- Dan DeSutter (Ind.
- Clay Mitchell (Iowa)
Following the broadcast, discuss with fellow forum participants how cover cropping can build soil health, improve yields, curb erosion, manage pests and build resilience into your farming system.