An alternate method for seeding annual ryegrass as a cover crop is drawing interest among Iowa corn growers and could reap dividends for the Oregon grass seed industry.

The method involves inter-seeding annual ryegrass into standing corn through aerial or high-clearance seeders.

The method was front and center at three field days in Iowa last month that were sponsored by the Oregon Ryegrass Growers Seed Commission in conjunction with the Iowa Corn Growers Association.

Corn growers in Iowa typically use cereal rye as a cover crop, in part because getting annual ryegrass established between the end of corn harvest and the beginning of harsh winter conditions is difficult and, at times, impossible, to accomplish. Cereal rye, a warm season crop, establishes faster than annual ryegrass.

When inter-seeding into small corn, however, annual ryegrass has time to establish before going dormant during hot summer months. It starts growing again when cooler conditions prevail in the fall.

The practice, which has been used for two decades in Quebec, Canada, was first introduced to Iowa farmers in 2012 by Midwest cover crop consultant Dan Towery, but to date is used sparingly there, according to Dan Zinkand, a cover crop consultant for the Oregon Ryegrass Commission.

More use of the practice could benefit Oregon seed producers, Zinkand said, given that 13.2 million acres are planted to corn in Iowa, making it the No. 1 corn-producing state in the U.S. The state has roughly 10 million acres planted to soybeans.

According to the Iowa Department of Agriculture, 907,000 acres in Iowa were planted to cover crops in 2018, a more than 50% growth from five years ago, when 350,000 acres were in cover crops, but still well below projected needs of the state’s voluntary Nutrient Reduction Strategy. The strategy is in place to help reduce nitrogen and phosphorus losses that contribute to the “Dead Zone,” or low-oxygen areas, in the Gulf of Mexico.

At the field days, held July 24-26, Iowa corn producers heard from several farmers who utilize cover crops in their cropping systems and were provided insights into inter-seeding.

Staff from the USDA Natural Resources Conservation Service also provided participants with information on the important role that permanent conservation structures like grassed waterways play in reducing soil erosion. Annual ryegrass, tall fescue and orchardgrass, three species produced in Oregon, are among the species seeded into grassed waterways in the Corn Belt, representing another opportunity for the Oregon seed industry, according to Zinkand.

The field days marked the third time the Oregon Ryegrass Growers Seed Commission has partnered with the Iowa Corn Growers Association on cover crop meetings in Iowa, dating back to 2014, Zinkand said.

“Working with Iowa corn makes sense, not only because it is the nation’s largest grower of corn, but also because annual ryegrass as a cover crop can help farmers meet the state’s Nutrient Reduction Strategy,” Zinkand said.

“I thought the field days were a complete success,” he added.