Grain farmers give cover crops a trial run

The use of cover crops in growing grain in Montana may be an idea worth pursuing in the Northwest.

So says Diana Roberts, Spokane-based Washington State University Extension area agronomist.

Roberts recently published an article for Spokane County Extension about the use of cover crops on Bob Quinn's organic farm in Montana.

The cover-crops approach would be important for organic farmers, but there are possibilities in direct-seed operations as well, Roberts said.

Quinn uses cover crops to supply nitrogen and manage his weeds.

Most farmers often use a fallow year to manage weeds, Roberts said. Cover crops are typically used in organic vegetable farming but hardly ever in grain farming, she said.

Cover crops are either disked into the ground before they mature or made into a duff layer to create a mulch to prevent evaporation.

A farmer would use the cover crop to compete with weeds, but reduces his input costs by growing his own fertilizer and drawing energy from the sun and moisture to create nitrogen in the soil, Roberts said.

Quinn uses the cover crop to provide nitrogen rather than bring in chicken manure, Roberts said.

Because a cover crop is in place, Quinn is not using a typical summer fallow period with constant tillage.

"He's taken care of a lot of the weeds before he plants his main grain, his cash crops," Roberts said.

Quinn's primary cash crops are winter wheat, spring wheat, barley, Kamut brand grain (an ancient relative of durum wheat tolerated by people who are sensitive to wheat), alfalfa, safflower and sunflower.

Though Roberts said it is fascinating to see what other regions like Montana are doing, those practices cannot often be exactly replicated in the Northwest region very successfully.

Quinn's farm in Montana is in an intermediate rainfall zone similar to the Davenport, Wash., area, Roberts said, but there are big differences. East of the Rockies, more rain falls in the summer, while the Washington region gets more rain in winter and spring.

Roberts said she is excited by the fact Quinn is growing cool-season cover crops like peas and camelina, which can be grown in the Northwest.

"I think it would be worth trying," she said.

Quinn also seeds his cover crops in the spring with a companion crop, cutting the cash crop and letting the established cover crops continue to grow prior to the fallow year.

Most farmers would think about seeding their cover crop in September and taking it through to June, but that would reduce the moisture in the soil and increase the risk of not germinating the cover crop, Roberts said.

Fred Fleming, who has a direct-seed farming system in Reardan, Wash., said his tour of Quinn's farm convinced him a cover crop for soil health needed to be incorporated into his system.

He said he hopes to increase the nutritional value of his soils to increase nutrients in his hard red winter wheat or hard red spring wheat, as well as have a comparable yield.

As part of a sustainable agriculture alliance, Fleming is looking for a reasonable rate of return. Cover crop practices will increase his cost of production, he said, but if the wheat has more nutrients and the marketplace recognizes it, he can get that rate of return.

As a direct-seed farmer, Fleming will use a roller-crimper to flatten the cover crop, killing it so that it decays on the soil surface and acts as a mulch, Roberts said.

Mowing the crop runs the risk that it may take moisture out of the soil away from the cash crops, she said.

Fleming said he is experimenting with the concept.

"I guess we're in chapter one," he said. "I understand there's 10 more chapters to be written."