Producers should be looking at three things when it comes to making cover crop seed purchase decisions:
What is the purity?
It is required by federal law that seed has a purity test to identify weed content percentages prior to being sold as a planting product – however, this is not the case if it is being sold as a feeding product.
“A lot of cover crops can be used as a seed product or feed product. In many cases where seed has been purchased for planting but sold for feeding, there has been a misunderstanding between both parties as to what the intended purpose was,” said Jerry Hall, director of research for GO SEED. “Unfortunately, this comes with consequences that can cause weed issues for years to come.”
When evaluating purity tests, producers should weigh the risks against what they are trying to achieve and if the weed is going to be controllable or not. If the seed is purchased with a purity test, producers also need to make sure the test matches the lot number stencilled on the seed bag.
“Attention to detail is paramount because one innocent mistake can introduce an herbicide resistant weed into your field,” Hall said. “And as simple as it sounds, even when you’ve ensured everything matches, it is still important to take a look in the bag before you dump it in the drill.”
Has it been tested for germination?
Federal law also requires seed being sold for planting to have a germination test, typically within a nine-month window ahead of selling. If the intention of use hasn’t been made clear to the seed merchant and feeding seed is received instead, then germination issues are likely. This is a common issue when it comes to peas.
“There are two common types of peas that get grown for cover crops. Winter peas are bred for forage and white flowering peas are mostly grain-types. Because the grain peas are typically much cheaper, they may be a more attractive option for someone wanting to cut seed costs. However, grain peas are extremely fragile, and germination can very much be affected by handling – just dropping the bag from waist height on a concrete floor can knock germination as much as 10 points each time,” Hall said. “So, even if the white flowered seed passed the germination test, throwing it on the ground from the back of a pickup truck could have damaged the germ.”
To further reduce any contamination or germination issues, seed should be purchased from sources that have adequately cleaned it. This will remove any lightweight and deformed seeds, improving germination and field uniformity.
For producers wanting to take extra precautions, Hall recommends buying seed early and conducting an on-farm germination test.
“Count out 20 seeds, drop them into paper towel, wet it, roll it up, and throw it into a Ziplock plastic bag,” says Hall. “Most of the stuff is going to germinate seven to 10 days. Before you ever put that seed in the ground you should have a good idea how it’s going to perform.”
Is it suitable for the local environment?
As certain cover crops come into fashion and gain attention from the success seen by different producers, they need to be evaluated on how they will perform on a farm or ranch’s unique environment.
“Matching a variety to the right soil type and area weather conditions can make the difference between a cover crop being a success or a failure,” Hall said.
Producers should be speaking to their neighbors about what worked well for them and what didn’t, and then doing their own trials. Hall also recommends utilizing the recently launched Cover Crop Information Map, which centralizes farm trial and industry research data into one location. Featuring an interactive map on gocovercrops.com, the free resource allows users to sort through raw trial data based on geographical location and 26 different topics.
“Speaking to neighbors and analyzing the raw data of industry trials completed in your geographical location is a good starting point to get an idea of what is and isn’t working in your area,” Hall said. “You can then take those findings and tweak them accordingly to your own objectives and unique challenges. I suggest planting an acre or two for the first year as a trial to see how it goes before running out and planting 1,000 acres in your first attempt. And continue to ask questions because cover crops require a lot of homework.”