Leopold Center for Sustainable Agriculture

Cover crops getting a second look due to drought

Back to Leopold Letter Fall 2012

Another Leopold Center research effort is providing valuable information as Iowa farmers respond to the drought. Fall-planted cover crops can reduce leaching of unused nutrients left in the soil after the dry, heat-stressed growing season. A cover crop also can help retain winter moisture and lead to long-term improvements in soil quality.

“This is a good opportunity to learn about cover crops so that the next time this happens, a farmer is ready for it,” said Tom Kaspar, soil scientist at the ARS-National Laboratory for Agriculture and the Environment in Ames. He works with the Iowa Cover Crops Working Group and the Midwest Cover Crops Council.

“We are telling farmers to start small, as with any new practice, and learn as they go. We always have nutrients left in the soil after harvest, but this year there are more nutrients than normal,” Kaspar said.

The Iowa Department of Agriculture and Land Stewardship will allow farmers to apply for cost-share dollars for fall-seeded cover crops. The emergency rule change includes cover crops as an eligible practice under the Iowa Financial Incentives Program (IFIP), administered by local soil and water conservation districts. Surveys show that only about 10 percent of Iowa farmers are using cover crops.

Depending on weather conditions, the latest planting date for cereal rye ranges from October 22 in northwest Iowa to November 14 in southeast Iowa. Seed has been more costly and difficult to find this year, due to increased demand and expanded corn production in North Dakota and South Dakota that supply small grains.

Cover crops reduce erosion and improve soil quality by increasing organic matter. Among the barriers to using cover crops are cost, the narrow window for fall planting, and how they could interfere with spring planting.

Back to Leopold Letter Fall 2012