Cover crop seeds range from beige to black, solid to striated, tiny and round to odd-shaped and bumpy. Mix them together and they're almost as colorful as Mardi Gras beads.
Cover crop seeds range from beige to black, solid to striated, tiny and round to odd-shaped and bumpy. Mix them together and they’re almost as colorful as Mardi Gras beads.
Making up this confetti-like array are some crops so old they’re new again and others that would traditionally pass for weeds. Increasingly, though, weeds are in the eye of the beholder, as no till growers experiment with upwards of 80 different plant species that can be used for carpeting the soil, producing forage and fostering soil biological health.
“One man’s weed is another man’s crop, to a certain degree anyway,” said Curt Sayles, a farmer from Seibert who is president of the Colorado Conservation Tillage Association.
Even kochia weed, the bane of farmers across the High Plains, has salvage value.
“It’s a poor man’s alfalfa,” joked Scott Ravenkamp, who farms near Hugo.
Like crabgrass, kochia is a “weed” that farmers have discovered makes surprisingly good forage, although it’s more palatable if swathed first, according to Jim Gerrish, a popular grazing consultant from Patterson, Idaho.
Farmers won’t start planting kochia on purpose anytime soon. But Sayles recalls that when renowned Australian soil scientist Christine Jones visited the area last year, it was the kochia that caught her eye and completely captured her fancy.
“You should do something with this plant,” he recalled her saying enthusiastically as the farmers around her cringed.
Jones was responding to the plant’s complex root system and the loose, granular structure of the soil surrounding it. Those qualities are evidence of vibrant soil biological activity, a goal of farmers who want to cultivate healthier land.
Sayles lamented Jones’ observation that many modern varieties of mainstream crops like wheat appear to have a diminished microbial response. By contrast, that’s where more traditional crops like rye or oats often shine.
Rye is a tenacious plant and has a notorious reputation with wheat farmers everywhere because it requires hand labor to remove once it gets into the crop.
“I’ve had to walk fields pulling rye,” Ravenkamp admitted. Even so, he’s quickly becoming a fan, noting that volunteer plants are relatively easy to control with rotational cropping.
“I’m fascinated by rye right now,” he said. “My rye is still green, even in the winter, and we have a huge window we can plant it in.”
The roots even appear to be fixing nitrogen, he says. He’s learned grasses will do that when there’s enough porosity in the soil for atmospheric nitrogen to get below the surface.
Another cover Ravenkamp likes is “black oats,” a traditional oat grass that mirrors another pest that continually vexes wheat farmers, cheatgrass.
Rye, oats and buckwheat are among as many as 80 different plant species sold in cover crop mixes by Green Cover Seed of Bladen, Nebraska. Owner and longtime no till farmer Keith Berns explains that these plants suppress weeds, with rye one of the best for controlling troublesome annuals.
“Mares-tail does not like coming up in rye. It will not do it,” he said during a presentation at the annual High Plains No Till conference in Burlington, Colorado. “The right cover at the right time can be very effective at out-competing weeds.”
Steve Tucker, who farms northeast of Holyoke along the Nebraska border near the town of Venango, has another term for it. He calls it “growing your own weeds.”
Numerous scientists and farmers like him are rethinking their traditional stance on weeds as invaders that need to be eliminated at all costs. “Sometimes weeds may not be as detrimental as we think they are,” Tucker said.
Kris Nichols, formerly with the U.S. Department of Agriculture Ag Research Service and now chief scientist at the Rodale Institute, echoed that idea.
“Learn to accept weeds that don’t really matter,” she told farmers at the High Plains No Till conference. “A lot of people are afraid to do a companion crop because, to them, it’s putting a weed out there.”
There’s debate over whether covers and companion plants rob water and nutrients from cash crops or whether the benefits to soil structure and water-holding capacity override those concerns. Nichols points out that today’s crops are, in some sense, the true weeds, in need of a healthy environment to thrive.
“We are growing things that aren’t really supposed to be grown here,” she said. “We are producing things not found in native landscapes.”
Where rainfall is limited, cover crops appear to work best when they can pay their way. Livestock feed is the most common way to add value. In other cases, farmers are growing soil-enhancing groundcover while harvesting the sunflowers that tower above them.
Ravenkamp has been able to harvest and sell ryegrass seed to customers in Oklahoma and Arizona.
Berns said farmers regularly approach him about growing seed for his company. When he and his brother Brian started out in 2009, they were only buying 10 to 20 percent of their seed directly from individual growers and the rest through brokers. Now those percentages are reversed, he said.
The first year in business the Berns sold enough seed to cover 2,000 acres. Last year, it was up to 350,000 acres. Other custom seed providers are also entering the market, which means demand should grow.