After a dreadful start to planting season due to the weather, producers may be looking for the silver lining in the clouds. Using cover crops — specifically cover crops for grazing — on their prevented planting acres could be what they seek, and could leave them with silver lining their pockets, as well.
Cover crops offer grazing and haying opportunities, can help anchor the soil, provide weed suppression and supply nutrients for soil health — all benefits for prevented planting fields, according to Dr. Rob Myers, an agricultural engineer with the University of Missouri Extension Office. However, he added that financial considerations are the main motivation behind cover crops.
“We are finding more and more farmers are reporting economic benefits to using cover crops,” he said.
Studies show cover crops produce the most financial benefit when part of a livestock grazing program, Myers added. When factoring in hay, fuel and labor costs, grazing cover crops can save producers upwards of $150 per cow, with the added benefit of improved nutrition and soil health.
“This summer, with the interest of having some forage, that’s probably the No. 1 reason for growing cover crops,” he said. “Either for summer grazing or haying this fall.”
Myers said erosion control and soil health are the secondary and tertiary, respectively, when it comes to cover crop priorities. He stated they can also help with herbicide-resistant weeds, which can save on costs, as well.
Additionally, counties in federal disaster declaration areas are eligible for funding to help pay for the cost of planting cover crops on fields that were flooded, he said. Producers can check with NRCS to see if they qualify.
Making a cover crop plan
Whether weed control, erosion control, taking care of moisture, or use as forage, producers first need to figure out the priorities. Stan Friesen, manager of Kaup Forage and Turf of Norfolk, Neb., stated producers can then backfill the timeline and determine the timing of planting, what makes sense for the grower and what species provide a benefit.
Friesen advised producers to answer a few basic questions before tackling cover crops:
- When is the earliest — and the latest — you can plant a cover crop?
- What will you rotate into next year? The next cash crop may determine whether the cover crop you select winterkills or can overwinter.
- Are you planting a cover crop for cover or do you want the potential of forage?
- How will you seed the cover crop you select? Will you broadcast the seed or can you drill it?
- What herbicide or fertilizer program did you use prior to claiming prevent plant? If you applied herbicide, make sure the covers are compatible. If you applied fertilizer, try to choose a cover crop that can cycle that nitrogen so it is not lost.
He also reminded producers to be flexible. With the increase in demand for cover crop seed this spring, supply of popular species is limited.
“When they can seed and when they plan to graze is the first option,” Friesen said. “Sorghum sudangrass is excellent for providing significant forage, but a frost will kill it, so unless it is seeded early (prior to Aug. 1) it will not produce a lot before being killed by frost.”
Brown mid-rib (BMR) has significantly greater feed value than conventional sorghum sudangrass due to increased digestibility, he added. Cowpeas are an additional option, a warm-season nitrogen producer. Teff is also popular; it is a warm-season grass that is best hayed, but producers graze it.
For August seeding, Friesen recommends oats, rye, brassicas (turnip and radish), crimson clover, hairy vetch and winter peas. September is ideal for winter rye, brassicas, crimson clover and peas.
Kaup also carries a multitude of other species, he said. Annual ryegrass, berseem clover, buckwheat, common vetch, lentils, rapeseed, red clover, sunflowers, sunn hemp, sweetclover, triticale and wheat.
“They all have a place depending on the customer’s goals,” Friesen explained. “They vary in categories like soil health, erosion control, drought tolerance, residue remaining and choking weeds, so we design a mix that will meet the needs.”
If the farmer wants to increase the feed value further and be able to graze later into the season, turnips, radishes and hybrid brassicas will continue to grow until the temps reach 15-20 degrees. They have high feed value, 30 percent protein, and extend the grazing season. Peas are another way to add additional protein to the grazing, as well as providing nitrogen.
Crimson clover has become very popular, as it will produce nitrogen in the soil and has a chance of surviving the winter under the right conditions, Friesen said.
“There is research out there showing eight or more cover crop species growing at the same time in the same place can create synergy not experienced with fewer species or monocultures,” said Aaron Hird, state soil specialist with the NRCS. “However, just what that positive benefit will be from the multiple species is difficult to say, as it can be different each year.”
There are also indications that growing a monoculture of a high biomass cover crop species, like a cereal grain or warm season grass, will be the most productive for biomass production and potential grazing, he said.
Nebraska NRCS has offered example cover crop mixes. Species included in one of the example mixes for Eastern Nebraska with an objective to provide supplemental forage while fighting erosion and competing with weeds were: Millet, sorghum, flax, lentils, safflower, oats, rapeseed, sunflower, soybeans and BMR.
To cover crop, or not to cover crop
The use of cover crops in row crop farming is becoming increasingly popular, especially in Nebraska. According to figures provided by the NCR-SARE Program, in 2017, producers harvested 15,119,256 acres of corn and soy beans (not including silage). That included 9,455,031 acres of corn and 5,664,225 acres of soybeans.
Nebraska farmers planted 747,903 acres of cover crops that same year. That covered 4.9 percent of commodity acres. While Nebraska ranks 24th out of 31 states in that regard, they showed a 109.3 percent increase in cover crop acres from 2012. That put them sixth out of all 50 states in improvement.
“There has been a great big increase in interest in cover crops,” said Leisha Roberts of Roberts Seeds, Inc., in Axtell, Neb. “We’ve been selling cover crops for years, but the last couple years have seen remarkable growth.”
So, why aren’t more producers jumping at the chance to save money and improve their soil health? Detractors speak of cost and cover crop failure.
Paul Ackley of Practical Farmers of Iowa stated that he saves $75 per acre in fertilizer costs due to using cover crops for grazing. The organic matter from the cover crop is enhanced by the “contributions” from the grazing animals themselves.
Ackley also said that cover crops save time and work. He said that he saves tons of top soil and doesn’t have gullies to fill in. Further savings can be found with the funding available to help cover costs of cover crops, including the Environmental Quality Incentives Program, Conservation Stewardship Program, State Cost Share and watershed-specific assistance programs.
As for crop failures, Jenny Rees, a UNL Extension Educator for York and Seward, said she has seen three main reasons:
- Newly planted seeds/seedling flooded out again by recent events.
- Planting method and machinery.
- Herbicide residual from previous crop(s) not allowing for germination or establishment of cover crop seed/seedlings.
The first, producers cannot help. The other two can be fixed.
Are you aerially seeding, broadcast seeding or drilling the seed? If you have irrigation available or farm in a region where moisture is plentiful, then aerial seeding or broadcast seeding is an option for many species of cover crops. However, not for all — some species, such as peas, soybeans and mung beans, perform much better if they are drilled into the soil. Also, if you live in a drier environment, then it is best to drill the cover crop to insure good seed to soil cover contact.
UNL Extension Educator Gary Lesoing cautioned that including cover crops in a rotation adds another layer of complexity that may be unfamiliar. Specifically, look at labels for herbicides applied in the previous growing season or any pre-emergent/post-emergent application earlier this season. The biggest things to look for on the label are: Plant back interval for the specific cover crop and the use rate related to plant-back intervals.
Rotation restrictions or plant-back intervals for herbicides will be key when selecting a cover crop to plant. These intervals indicate the length of time after herbicide application that another crop can be planted. It is important to note that this is different from the grazing or forage restrictions posted on an herbicide label for crops to which an herbicide is directly applied. If the forage cover crop species you intend to plant is not listed on the label, you must follow the rotation restriction listed for “other crops.”
Retired UNL professor Bruce Johnson said that the outlook for cover crops is good, but it depends on getting larger producers to commit to the idea.
“Larger crop producers might be reluctant to complicate their system since timing is of the essence in both planting and harvesting,” he said. “But it means a much harder effort to get significant farmer buy-in to move in this direction if the largest producers are not interested.”
Jon Burleson can be reached at email@example.com.