No-Tillers Finding New Ways To 'Cover Up'By Martha Mintz, Contributing Editor
Cover crops are going mainstream in production agriculture, which means more people are working to make them succeed. This should be good news for no- tillers, who are increasingly relying on cover crops to scavenge nitrogen and improve soil quality and water infiltration in their fields.
But deciding on the best way to seed cover crops can be difficult.
The best seeding method is often drilling, experts say, but no-tillers try- ing to do that after harvest find it’s usu- ally too late in the season to achieve optimal establishment.
No-tillers have also expressed frustration with the results with aerial seeding, as they’ve complained about uneven distribution or seeds getting caught in standing crops and never reaching the ground.
There’s even been talk of pelletizing cover-crop seeds to help them push through crop canopies.
“But the general reaction I’ve seen is that producers don’t want to pay for additional weight,” says Joel Gruver, soil scientist at Western Illinois University. “They just want to pay for pure seed.”
Consequently, cover-crop seeding machines are rolling out of farm shops throughout the country.
Usually consisting of converted spray rigs that tower over growing crops, these rigs can bypass the canopy and spread seed evenly on the ground.
“Now that cover crops are going mainstream, we have more sophisticated operators applying their expertise and capital to solving cover-crop problems,” Gruver says.
High-Boy Home Run
Loysville, Pa., no-tiller Charles Martin made his foray into high-clearance seeders in 2009. He used a highboy that can be raised from 6 to 9-1⁄2 feet in the air to seed cover crops into standing corn and soybeans.
The rig runs on an 85-horsepower engine and has a 45-foot-wide boom that covers 18 rows on 30-inch spacings. The sides can be adjusted to level the platform on hillsides.
Four-foot-long drop tubes place the cover-crop seed beneath the crop canopy. Martin has seeded clover, ryegrass and various mixes of small grains.
“From work done with this seeder last fall, the coverage is as good as if the cover crop were sown with a grain drill,” he says. Martin is already taking his seeder out on other farms, including that of Lancaster, Pa., no-tiller and cover-crop expert Steve Groff.
Groff had Martin seed cover crops in 2009 and 2010. While Mother Nature threw them some curve balls, Groff thinks there is great potential with these types of machines.
In 2009, they seeded too early and the cover crops wouldn’t establish under the dense canopy. In 2010, rain showers got the cover crops started and then a hot, dry spell burned them up.
“I’m still promoting this practice because I know it works when conditions are right. We just got unlucky 2 years in a row,” Groff says. “In the long run, I think it will widen the window of opportunity for seeding cover crops and be a great option for broadcasting cover-crop cocktails, such as tillage radish, annual ryegrass and crimson clover.”
In the past, Groff has seeded a radish and annual ryegrass mix with a spinner into standing soybeans. While he got good germination, there were distribution issues.
“Ryegrass seed is lighter than tillage-radish seed, so it doesn’t spin out as far, resulting in uneven distribution of the different seeds,” Groff says. “With the high-clearance seeder’s tubes, the seed ratio of the different covers is the same the whole width of the seeder.”
He says Martin’s high-boy rig is something to see.
“It has slope control for the booms, all-wheel steering — the term contraption doesn’t do it justice,” Groff says.
It’s possible for no-tillers to have a machine that not only does one thing, but two, three or more. That is what’s offered by a prototype rig produced by a group of Canadian collaborators.
Daniel Briere, agronomist; Bertrand Gregoire, independent machinery consultant; Francois Tetreault, Quebec farmer; and Quebec’s exclusive sprayer dealership, Agritex, teamed up to build a multipurpose cover-crop seeder.
The prototype is a fully functioning sprayer that, with a few attachments, can knife in fertilizer, spread granulated lime and seed cover crops into standing corn.
“Three years ago, there was a need to increase air in the soil to boost soy- bean yields,” Briere explains. “We were having major compaction issues and several solutions were recommended, but planting an annual ryegrass cover crop drew a lot of attention.”
Initially, they tried aerial seeding, but a month-long drought in September led to a poorly established cover that didn’t overwinter. But knowing the benefits of an annual ryegrass cover crop, Tetreault wasn’t ready to throw in the towel. He went to consult with Briere and Gregoire on an idea.
He wanted to create a machine that allowed him to spray his crops in the spring and seed annual ryegrass later in the season.
They started in the winter of 2009 with a used John Deere 4720 self-propelled sprayer. At Agritex, they worked to modify the sprayer base, adding a 3-point hitch on the front of the machine and hydraulics to manipulate wheel spacing.
“Twin rows are popular here, so we wanted to be able to adjust tires to fit between standard 30-inch rows or twin rows,” Gregoire says. “We can adjust the wheels hydraulically from a 120-inch width to 150 inches.”
The 3-point hitch is where the seed hopper and blower are mounted, allowing for a fairly quick hookup when changing from spraying to seeding. Aulari provided and installed the seed hopper and blower.
The hopper and a reserve tank hold about 1,500 pounds of ryegrass and is fitted with a scale that tells the operator in the cab how much seed is left. Below the seed tank is a blower that blows seed through large tubes to the back of the sprayer.
Seeds hit another blower at the boom that distributes seed equally to each outlet, and yet another blower pushes seed through each outlet and to the ground.
The boom is 100 feet wide and has 41 dropped hoses that go between rows and under the canopy to seed 41 rows. The tubes run about 1-1⁄2 feet off the ground and have a distributor at the end to spread seed equally across the width of the row.
“One of the biggest issues with aerial seeding was that we ended up with bad coverage when using the light seed,” Gregoire says. “You get really even coverage with this rig.”
Being able to use the rig as a sprayer and a seeder should help Tetreault cover the cost of the machine.
“He’ll be able to spray in the spring and then spread cover crops for himself and neighbors, as the window for application is wide,” Gregoire says.
This rig has a 5-foot clearance and is used for earlier cover-crop seeding than some rigs in the United States.
“We’re still working on when the best time to establish cover crops is,” Briere says. “We don’t want them to jeopardize yields, but we want them to establish. That means they need about 60 days of growth before a hard frost. Here that happens in mid-December.”
With aerial seeding, they tried the beginning of September, but a drought meant poor germination. By seeding with their rig earlier in the season, cover crops are given a better chance.
“We’re trying to time seeding when corn is about 5 feet tall and the leaves haven’t covered the row,” Briere says. “The seeds are able to germinate and establish while there’s still light, and then sit there as the corn continues to grow, not really competing because it’s not actively growing.
“Then, when the corn starts to dry down and light hits between the rows, the cover crop takes off again.”
Timing seeding before tassel means there’s no cob to damage when running the machine through the field. They used the machine to seed some annual ryegrass in a field in Saint-Pie deBagot, Quebec.
The field was seeded on August 31 at 30 pounds per acre and they achieved good establishment.
“We found that the results were better in 30-inch rows as opposed to 30-inch twin rows,” Briere says. “Because of the canopy in twin rows, we may need to look at earlier seedings.”
The group is looking forward to researching and honing in on the best timing for seeding.
A Multi-Use Tool
For added utility, the Quebec group also created a 12-disc toolbar that can hook up to the front 3-point hitch and knife liquid nitrogen 1-1⁄2 inches deep. “If it’s windy, no-tillers can put the nitrogen directly into the ground. If it’s calm, they can use the same machine to spray nitrogen,” Gregoire says.
It’s this versatility that can be added to each spray rig that he hopes will help him sell more sprayers at Agritex. “Many producers think it’s too expensive to own their own self-pro- pelled sprayer, but if you can get a machine to do multiple jobs, it spreads out the investment,” Gregoire says.
Farmers in the area are definitely interested, with 160 producers showing up for a December meeting to view the machine.
“We’re always interested in sharing our knowledge and we really want to develop a system that works in our area,” Briere says.
There’s a lot of chatter online about cover-crop seeding rigs, which is helping to boost this grassroots machinery movement.
“Forums are changing the way farmers talk to farmers,” Gruver says. “They used to only share ideas with a narrow community of people. Now, through forums, they’re able to communicate and share ideas more broadly.”
Forums such as the No-Till Farmers' Forum and AgTalk bring farmers from around the world together to share experiences, bounce ideas off of other producers and get help with issues. Such a forum got Roanoke, Ind., farmer Andy Ambriole started on building his own cover-crop seeder.
After seeing posts on the topic, he began to build a seeder to seed cover crops into corn and soybeans.
He got a SARE producer grant and went to work, starting with a Hagie STS12 self-propelled sprayer he already owned.
He removed the tank and fitted the Hagie with a used Gandy Orbit Air seedbox. It was a ground-drive seeder, so he had to spend some time converting it to a hydraulic drive.
It took 1,500 feet of hose to plumb the outfit, which has 90-foot booms with drop tubes for 36 rows.
Each is fed by an individual metering wheel.
“I don’t have an engineering degree. I just saw an idea and thought it was something I could do,” Ambriole says. “It took tinkering and a lot of trial and error, but it wasn’t rocket science.”
Ambriole farms 1,700 acres of wheat, corn and soybeans with his father. They have about 255 acres of organic crops that they had used cover crops on before.
“I had interseeded clover into wheat and drilled cover crops like annual ryegrass, buckwheat and radishes,” Ambriole says. “I built this seeder because I wanted to be able to get across more acres and give covers more time to establish.”
He had drilled some annual ryegrass into corn, but it was a struggle.
“Harvest is a busy time. You don’t need another thing to do, like planting,” Ambriole says. “With the seeder, I can start in mid-August, which is a slow time of year.”
In 2010, he seeded in August and corn varied from completely dead with grain at 25% moisture to corn that hadn’t black–layered, yet.
“Ideally, I’d like to plant when the lower leaves are dried down and light is starting to get through the canopy,” Ambriole says.
He uses a lightbar system to guide and act as a row counter. With 72-inch clearance, he bends the corn back a little bit and runs over a few plants on the end rows.
“The damage was nothing com- pared to what I thought it would be,” Ambriole says. “Anything I did run down, I was able to pick up easily with the corn head. The corn bends a bit when I go through, but it bounces right back.”
Ambriole considered going for the higher clearance of other rigs he’d seen online, but he’s glad he stuck with the 6-foot clearance.
“It helped keep the unit affordable and it’s more stable on hills,” he says.
It took around $15,000 to $20,000 for Ambriole to convert his sprayer. He plans on charging between $11 and $15 per acre for custom application, just over the cost of aerial applications.
It was a trial season for Ambriole in 2010. He seeded radishes, ryegrass, a ryegrass-clover mix and a radish-ryegrass mix into corn and soybeans. Despite being dry from August through November, he says the results have been fairly positive.
“I was surprised even with drought conditions that the cover crops came up and sprouted pretty well. They got a good start and I’m eager to see what survives the winter,” Ambriole says.
In-crop seeders aren’t the only players in the cover-crop game. There are other options being explored for improving cover-crop seeding techniques.
“There is the option of putting a seeding device directly on the combine to drop seed right behind the header or behind the combine,” Gruver says. “There is commercial equipment available in the United Kingdom to do this.”
Seeding with the combine would place seed underneath residue and turn two field operations into one.
“The challenge is that most farmers don’t want anything slowing down the harvest, so dealing with restocking seed or checking on seeder performance is an extra wrinkle most of them don’t want to mess with,” Gruver says.
Yet another combination option is seeding cover crops with manure slurry.
Tim Harrigan, Michigan State University assistant professor of biosystems and agricultural engineering, and other Michigan State scientists have been working on just such a system since 2003.
Manure slurry-enriched seeding is conducted by equipping a slurry tanker with a rear-mounted, rolling-tine aerator and an SSD (subsurface deposition) slurry distribution system.
The rolling tines slightly disturb the soil, then seed mixed with manure in the tank is dropped into the fractured soil behind the tines.
While this seeding system results in fewer plants per area than conventional seeding — about 30% to 70%, according to Michigan State — each plant produces more biomass.
Michigan State reports that biomass yields of oilseed radish, oriental mustard, annual ryegrass, cereal rye, oats, wheat, forage rape and forage turnips sown into untilled wheat and corn-silage stubble with swine, dairy and beef slurries from 2004 through 2006 were equal to or greater than a conventional planting.
The system has been shown to work better in untilled ground, making it a potentially viable option for no-tillers.
A Triple Threat
Terry Taylor, a no-tiller from Geff, Ill., has been using cover crops in his no-till corn and soybeans for many years.
He’s used annual ryegrass, cereal rye and hairy vetch for 20 years. But his biggest challenge is covering his 2,000 acres quickly.
His solution is an 1860 John Deere air seeder with two Deere 1900 hopper carts and a Gandy seeder added on.
This setup allows him to pull from field to field without slowing down to change out to a different cover crop.
He typically puts hairy vetch in the front tank, annual ryegrass in the back tank (sometimes mixed with crimson clover) and then radishes in the Gandy.
Taylor plumbed the Gandy to run individual lines to every fourth opener to get 30-inch radish rows between the other seeded crops. Radishes are only seeded as a companion to the other crops, at a low rate of 2-1⁄2 pounds per acre.
“This system gives me the ability to choose between two different seed options and the ability to add radishes to the mix,” Taylor says.
He used the rig for the first time this fall to seed 1,000 to 1,500 acres of cover crops.
He picked up the air seeder for an affordable cost because it’s on 7-1⁄2-inch centers, and because narrow-row soybeans and wheat are falling out of favor in his area.
Before, he had used a regular drill or a Philips harrow with a Valmar seeder on it.
“We went with this type of machine because it speeds up our cover-crop planting operations and we get more consistent seed-to-soil contact than other options,” Taylor says. “The cover-crop seeders that plant into crops lay seed on top of the ground, where it may or may not germinate.
“The downside to my seeder is I have a later cover-crop planting date.”
For Taylor, he’s far enough south in Illinois that he’s able to get cover crops planted a little earlier than other parts of the Midwest, usually getting in the field by mid-September.
Looking To The Future
Gruver warns there will be some additional challenges along the way as no-tillers move forward with cover- crop seeding.
Residual herbicides, for example, could ruin even the most perfectly seeded cover crop.
“We’ve been so heavy in glyphosate systems that residual chemistry hasn’t been a concern, but with resistance issues, a lot of people are going back to residual chemistries,” Gruver says. “That’s a real concern if that chemistry is active against a cover crop.”
Gruver still has confidence that cover-crop seeding techniques will move forward because of onfarm research and determination.
While not everyone has the time, money or expertise to build their own machine, there’s still a chance no-tillers can put these cover-crop seeding innovations to work on their farms.
Most believe the machines will become increasingly popular for custom seeding, with producers renting out their machines to cover their costs.
“Cover-crop management systems have to be customized for different farms with different farming systems in different areas,” Gruver says. “This type of research and development will not be done by industry, like you see with Bt corn technology. We need innovative farmers to lead the way.
“The no-till farming community definitely includes the types of innovators with the skills and the mindset to figure out how to make cover crops work. They’re well-prepared to take on the cover-crop challenge.”