Cover Crops Improve Soil Health and Increase Forage Production
The benefits of creating a diverse ecosystem within a field.
Calvin Gavelin is the third generation on his farm near McCord, Sask., Canada, where he grows a variety of cover crops — annuals, biennials and perennials.
“Our perennial stands may have up to 20 species of a diverse blend,” he says. “The goal is better soil health, and we get about 10 years out of those stands. They have been very productive. Last year all our cover crops were about double our monoculture stands in volume, and our cows prefer the cover crops when grazing.
“When we harvest a cover crop for green feed, we leave about 8 to 12 inches (in.) — to leave enough stubble to be healthy,” he continues. “It’s tall enough to catch snow in winter or provide green feed for wildlife.”
Gavelin started seeding more cover crop mixes in 2019 after taking a holistic management workshop.
“That’s when we created a grazing plan with cover crops and intercropping,” he says. “That first year we got completely hailed out — not only the cover crop, but also 700 acres of monoculture durum wheat. The cover crop — a seven-way blend — came back from the hail damage and grew enough to feed our cows all winter. We swath-grazed it because it wasn’t mature, but it had tremendous productivity and changed our operation completely.”
Blends of different forage species are like little ecosystems and are more sustainable in a drought, Gavelin says. The diversity gave the crop productivity and hardiness. It was an eye-opener for Gavelin and others in the area.
When the crop adjusters came out to assess the hailed-out durum, Gavelin showed them the cover-crop fields. The productivity of those plants compared to the other fields that were treated the same way and couldn’t handle severe conditions was mind-boggling, he says.
His farm is now part of a living lab study in Canada with the diverse blends he uses for cover crops. In some of the fields, Gavelin is using up to 20 different species, including warm- and cool-season grasses, legumes, cereals, brassicas, etc. The most noticeable change is a healthier ecosystem with more birds and a diverse insect population, he says.
In 2022 a plague of grasshoppers hit the area. His cropping practices seemed to fend off the insects better, says Gavelin. “We didn’t have as many grasshoppers. We had more variety of insects, including some that prey on grasshoppers. We are creating a system that is very resilient.”
He also uses intercropping — growing two or more different crops together — on his farm. He seeds barley and hairy vetch together. The hairy vetch supplies nitrogen for the barley, and the barley gives the hairy vetch phosphorus. Gavelin says by using intercropping, he yields about 9 bushels more than when using synthetic fertilizer.
“When we seeded our durum, we also seeded winter wheat,” he explains. “This helps with two goals. One is to keep a living root in the ground until freeze-up, to have healthy soil. Two is that on a normal year this supplies fall grazing for our cattle on land that would typically sit idle. We plan to do more of this kind of interseeding in the future.”
Editor’s note: Heather Smith Thomas is a freelance writer and cattlewoman from Salmon, Idaho. [Lead photo by Kevin Elmy.]
