POCATELLO, Idaho—Steve Shibely sprinkles in a bit of radish seed before he plants his winter wheat.
For a $12 per acre seed investment, the Mud Lake, Idaho, farmer believes his experiment with a so-called companion crop has improved soil moisture penetration, saved him on fertilizer and slightly boosted his yields.
Shibely participated in a panel discussion on cover crops—crops planted solely for soil health benefits—during the recent 47th Annul University of Idaho Potato Conference in Pocatello.
Cover crops have been catching on throughout Idaho, but Shibely considers himself a pioneer within his region in companion crops, which contribute soil health benefits even as he raises a cash crop.
The radish roots scavenge for nitrogen and other nutrients that may be inaccessible by wheat. Radish dies in the winter and slowly releases nutrients for the grain as it decomposes.
“I think there’s a lot of room for (companion crops) to grow here and a lot of people aren’t aware of them in this area,” Shibely said.
In a comparison of adjacent fields both following potatoes, Shibely said the field with radish companions required 35 units of nitrogen less than the field of winter wheat alone, and enjoyed a 4-6 bushel yield advantage.
Shibely has also been stepping up his no-till acreage and has seeded wheat directly into a prior cover crop of radish and triticale.
Aberdeen, Idaho, farmer Doug Ruff finds when he can get his mustard cover crop seeded by Aug. 10, following winter wheat, there’s a lush stand to disc into his soil for an organic matter boost by October. He said hot mustard also acts as a natural fumigant to control verticillium wilt, though he doesn’t view it as a replacement for fumigation in susceptible varieties such as Russet Burbank. When conditions make it impossible to plant his cover crop in time, he irrigates harvested winter wheat to produce a volunteer grain cover crop.
“The area we farm, like a lot of Idaho, came out of the desert. There’s not much organic matter,” Ruff said.
Bill Meadows, owner of Mountain States Oilseeds in American Falls, suggests growers try raising a volunteer cover crop following commercial mustard.
Aberdeen farmer Rob Giesbrecht has been raising cover crops since 1995 and advises growers it’s a longterm investment in soil health.
“If you’re going to do it, commit to it. Don’t just put seed on and forget about it,” Giesbrecht said.
He also recommends that growers start small with cover crops.
Ray Archuleta, a soil health specialist with USDA’s Natural Resources Conservation Service in Greensboro, N.C., promotes planting a diverse mixture of cover crops to derive a broad array of benefits. Barley, oats, and cereal rye, for example, contribute high amounts of carbon to soil. His potato growers have enjoyed the greatest success by rotating spuds every other year with a multispecies cover crop.
Archuleta advises against tilling cover crops into soil, which disturbs organic matter gains, and suggests no-till farming, whenever possible.
“Once you understand soil function, you cannot exclude cover crops,” Archuleta said. “Cover crops are not optional.”
Source: www.capitalpress.com