Editor's Note: This article was published by the Grant Tribune Sentinel.
Not only can cover crops planted in no-till fields fix nitrogen in the short term, they can also reduce soil erosion and mitigate the effects of drought in the long term, says a Natural Resource Conservation Service agronomist.
"Cover crops have always been valuable for erosion control," says Barry Fisher, NRCS Indiana state agronomist. "But if we look at it from a no-till standpoint, especially a never-till standpoint, cover crops have a whole new host of benefits that they never had in conventional tillage."
Among the benefits Fisher listed included:
They give us the ability to build vertical soil structure.
They build deep macropores in the soil, which allow more water to penetrate during the winter months.
They're at work when there's nothing else out there working on the soil.
"For years, we've known that competition from the cover crop alone helps control weeds," Fisher says.
He adds there's a lot of evidence that some of the oilseed radishes, brassicas and annual ryegrass are very effective at controlling soybean cyst nematode and other pests.
Some producers are aerial seeding cover crops directly into standing corn or soybeans sometimes in September, fisher says, so that they can get it established but not create a problem with harvesting the cash crop.
Fisher advised producers to time the cover crop with the cash crop so that it can conserve and trap nitrogen and protect the soil from erosion during the fallow period.
"If I were going to harvest these crops, I would do it through an animal," he says. "Certainly there's a good opportunity, especially in this part of Nebraska where grazing cornstalks is very much a part of the culture, for having a cover crop to provide extra nutrition and also a network of roots to support the hoof traffic."
Fisher doesn't think of these cover crops as another cash crop, though. Instead, he's focused on the benefits to the soil, trapping nitrates and nitrogen during the off-season.
"Tests show that a lot of the cover crops can scavenge 60 to 70, maybe as much as 80 pounds of nitrogen per acre," Fisher says. "That's the immediate economic payoff for growing these crops."
Soil quality is a long-term benefit, he says. Cover crops provide risk protection in dry, hot years; they build soil nutrients and better biological activity.
Post a comment
Report Abusive Comment