New field guide helps farmers choose, manage cover crops
Farmers interested in planting cover crops to improve soil health can now find information and tips in a new pocket guide produced by the Midwest Cover Crops Council and Purdue University.
Written by Eileen Kladivko and Corey Gerber of Purdue's Agronomy Department and colleagues from Michigan, Ohio, Iowa, Wisconsin and Ontario, Canada, the goal of the Midwest Cover Crops Field Guide is to provide information to farmers that will help them choose the appropriate cover crops for their needs and learn how to best manage them to receive the most benefits. "Interest in cover crops has been increasing across the Midwest over the last 2-3 years, especially in the eastern Corn Belt of Indiana, Ohio and Michigan," said Kladivko, a professor of agronomy. "Planting cover crops can help with weed suppression, breaking up compacted soils, erosion control, and, over the long term, improving crop yields and profitability. So demand for information about cover crops has been increasing as interest increases."
The guide is available through the Purdue Extension Education Store at www.the-education-store.com or by calling 888-EXT-INFO (398-4636). Individual copies of the guide will cost $5 each, and boxes of 25 will be available at a 10 percent discount, $112.50.
The guide is divided into two sections. The first contains general information about cover crops, including selection and planting methods, killing methods, concerns about insects, and ways to keep the crop from becoming a weed. The second contains photos, seeding dates, depth, planting and killing methods, benefits and cautions for specific crops, each given a ranking according to their benefit type and amount.
Cover crops are planted after harvesting a cash crop, such as corn or soybeans, or sometimes shortly before harvest to conserve soil nutrients and prevent erosion during the winter. Each cover crop is cultivated for a specific benefit: grasses such as annual ryegrass and wheat, for example, break up compacted soil, while legumes such as alfalfa and clover "fix" atmospheric nitrogen and convert it into a form plants use.
Types of cover crops are selected according to the needs of the soil and cropping system, and they are either killed off or allowed to die naturally to release nutrients into the soil before or during the main growing season.
Farmers faced with high fertilizer and pesticide prices want to be efficient and conserve as many nutrients in the soil as possible, Kladivko said.
"Cover crops trap nitrogen that would otherwise leach away in the fall, winter and spring," she said. "By planting cover crops, farmers can save 20 or 30 pounds of nitrogen that would otherwise have been lost. This will help build soil organic matter, and in the long-term it may reduce their fertilizer rates or produce a higher yield for the current fertilizer rate."