We hear a lot of cover crop success stories. They clearly have a lot of advantages- if you can get them right. Cover crops reduce erosion, can increase yields, increase the organic matter in your soil, can allow you to cut back on fertilizers and herbicides, improve no-till transitions, improve the water infiltration and holding capacity of the soil, and help limit runoff. But reaping these benefits takes a lot of hard work, research, and trial and error. If you’re not convinced yet, try reading another success story, consult the Cover Crop Resource Guide, and get started with cover crops.
Janelle Atyeo of Corn and Soybean Digest shares a yet another successful implementation of cover crops on a South Dakota farm. Brian Johnson farms with his wife and parents south of Frankfort. They now successfully grow cover crops of leafy radishes and sorghum Sudan grass after harvesting oats. All of this to prepare for a healthy corn crop the following year. The nutrients from the cover crops will help his corn get a strong start.
The Johnson operation is no-till, and they’ve farmed that way for 30 years. They work their fields with a method called bio stripping.
He aims his seed within the 2-inch row where the cover crops are growing now. That’s where they’ll land in the softest soil. When the corn or soybeans put down roots, they’ll follow the holes where radishes grew deep into the soil before turning to mush with winter’s freeze. Wheat straw residue next to the planting strip holds in moisture and shades the ground until the corn canopies.
The Johnsons consult NRCS District Conservationist Shane Jordan for recommendations. The next step for their operation seems to be grazing cattle on the residue after harvest. They’ve already made more pasture by putting their least productive ground back to grass. This was not commonly done 10 years ago, when grasslands were plowed to plant crops because prices were so high.
The Johnsons appear to be doing it right, and make it look easy. All we seem to hear about covers are the benefits. But the truth is, that it’s often times not easy. AgWeb has published a Cover Crop Resource Guide from Farm Journal Media, that provides a great deal of information without the sugar coating.
For farmers, planting cover crops means more management, not less. You might not see the benefits for several years after starting. You need to change things up each season to address your specific goals, and make sure that you’re planting good covers at the right time for your region that will meet your needs.
Where to start? If it’s your first go with cover crops, choose one that’s easy to manage- like oats and radish- and only plant a few acres. To more easily compare the impacts, plant in replicating strips.
Splitting a field in half is better than nothing, but it’s hard to get an accurate evaluation without replicated strips.
Farm Journal Field Agronomist Ken Ferriend recommends regularly assessing your soil.
“Your soil physical provides a benchmark so you can follow up later and see if soil health is improving.”
“The good news is, soil will improve every year you grow a cover crop,” Towery adds. “How soon you see measurable yield improvement depends on field history and what limiting factors, such as weather, are present in a year. For example, soils that are low in organic matter will benefit faster from cover crops.”
Allow your goals and planting window to guide you through cover crop seed selection, says Dan Towery, a crop consultant for Ag Conservation Solutions in West Lafayette, Indiana.
Even after you’ve read everything possible and talked to experts and fellow farmers, you’ll have to roll with the punches to work around the weather and production conditions, Towery notes. For example, if you’re having wet weather in early September, you might need to adapt and go to aerial seeding instead of planting after harvest.
Planting too late is the most common rookie mistake. Cover crops planted too late may still come up, but don’t establish and winterkill. Be willing to adapt and change your plan depending on conditions.
“One Illinois grower planned to fly a cover crop of annual ryegrass and radishes into standing corn between Oct. 1 and Oct. 15,” Ferrie says. “But his seed provider advised not planting until he reached 70% light penetration on the ground. Because planting was late, it was early November before that happened. Only one cover crop fit the planting window—cereal rye.”
Another thing you might want to consider is planting a mixture. They typically outperform a monoculture.
“Mixtures add more diversity, grow at different times, better compete with weeds and optimize nutrient cycling,” says Dwayne Beck, manager of South Dakota State University’s Dakota Lakes Research Farm.
There’s definitely a lot to consider. But if you can improve your soil health, boost yields, suppress weeds, and provide nitrogen, it’s probably something that you should spend some time getting a handle on. Read our article about planting green cover crops here.
Image courtesy of Norfolk Daily News