Cover Crops: Long-Term Benefits and Cost

Planting a cover crop could potentially improve yields on corn by 3.1 percent, and 4.3 percent on soybeans. These were the findings of 1,900 farmers in the USDA’s North Central Region Sustainable Agriculture Research and Education program in 2014.

This is just one of the many benefits derived from the use of cover crops, including a way to reduce erosion, improved ability to hold water, nutrient management, build organic matter and soil structure.

The use of cover crops had increased by 50 percent to a total of 15.4 million acres according to the 2017 Census of Agriculture. The census also showed that a number of states including Missouri, Illinois, Ohio, Mississippi, Nebraska, Vermont, Arizona with Iowa leading the way with a 153% increase.

“Getting significant additional growth in cover crop adoption will take [a] continued interest by farmers and a coordinated effort among many different partner organizations and agencies, which I believe we can accomplish,” Dr. Rob Myers, director of Extension programs for North Central Region SARE, speaking to Morning Ag Clips regarding the increase. “The need for additional protection and improvement of our nation’s soils is paramount, as our whole food system depends on having healthy soils.”

Benefits –

  • Cover crops can keep costly nutrients from running off into the water.
  • They can help with water retention. As Ray Gaesser, president of the American Soybean Council notes, “When we started planting cover crops, we eliminated erosion that was a result of those rains.” Every year since 2010, his farm has received 4 inches of rain in one hour. Soybean yields increased 11.6 percent, and corn yields increased 9.6 percent in the drought year of 2012 following the use of cover crops versus no cover crops. The figure was part of a cover crop survey conducted by Conservation Technology and Information Center and funded by SARE and the American Seed Trade Association.
  • In addition to nitrogen, cover crops make potassium and phosphorus available. The planting of radishes can reach up to 6 feet and bring deep-lying nutrients closer to the surface for cash crops.
  • Cover crops can provide excellent weed control.
  • Planting cover crops is one way to convert them into dollars through animal grazing. Cover crops planted in late summer can be used for grazing ground for cattle in the winter. As Kent Vlieger, NRCS State Soil Specialist states, “Those cattle are ‘fertilizing machines.’ They take that [cover crop], they process it…and it’s great for next year’s crop.”
  • Conservation and sustainability, or as it is becoming to be known as regenerative agriculture. Consumers are asking for sustainability, and cover crops help to sequester carbon.

Costs –

Perhaps the most significant costs associated with planting a cover crop are seed and planting costs. A paper by farmdoc daily titled Understanding Budget Implications of Cover Crops gives an estimate for the costs of establishing a cover crop. The largest expense will be the seeds, depending on what type of seeds and the seeding rate. The Northern Great Plains Research Lab in Mandan, ND has a chart which shows the types of cover crops, which types are best for your soils and seeding information. Aerial seeding is more expensive than drilling but allows flexibility with timing and allows seeding into the standing crop before harvest. The university estimates that the cost for drilling is $13.40 per acre. For the cost analysis, they looked at a cover crop of 60 pounds of cereal rye and a second blend 15 pounds of hairy vetch and 45 pounds of cereal rye per acre. Based on seed prices in central Illinois, the total cost including drilling was $28.40 per acre solely with the cereal rye and $58.25 per acre with the blend.

However, some of these costs can be offset by a carbon credit. The same study found that cereal rye can recover 25-50 pounds of nitrogen for a credit of $5-$13 per acre. For the hairy vetch/cereal rye blend a recovery rate of 50-100 pounds before a corn crop for a credit of $10-$26 per acre (SARE 2013). Additionally, some cost could be funded through the Environmental Quality Incentives Program (EQIP) and Agricultural Management Assistance (AMA) program administered by the USDA Natural Resources Conservation Service (NRCS).

Long-Term Solution

“It’s like a new crop, there is a learning curve behind it. There are certainly advantages no matter what your current crop rotation is; there is a way to work in cover crops,” said Vlieger. “Whether you want weed control issue, you’re looking at some cereal rye to get ahead of the weeds. You have some erosion issues, or you are looking to build organic matter. All those are going to have cover crops that you are looking to focus on in your operations.”

Implementing a cover crop program is a long-term decision. While the initial cost may be somewhat high and add already to the razor-thin margins, you have to consider the valuation of the benefits. Those benefits include reduced soil erosion, water quality,  improved soil health, potential yield improvements, and grazing for livestock. Three-quarters of farmers in a survey conducted by RABA research, state that farmers are aware of the negative impacts of agriculture on soil and water resources and there should be an incentive to reduce runoff and soil loss. In addition, the survey stated farmers support research for ways to reduce costly chemical inputs to increase profitability. Cover crops could be the tool for sustainability to deal with some of these issues on the farm.