Cover cropping is certainly the hot topic of the last two years, with lots of interest in everything from traditional oat and red clover covers to multi-blending and inter-seeding covers into standing crops. Recently, Twitter has been alive with photos and links, and with descriptions of progress and the impacts of various cover crop regimens.
As summer arrives, Country Guide put together a grower panel on cover crops, featuring four producers from across Eastern Canada. Each is from a different region, with specific rotations, farming operations and level of experience working with cover crops. Yet all are united in their belief that covers provide a unique benefit to their crop performance and overall soil health.
For this discussion, we invited:
Laurent Van Arkel, a grower from Dresden, Ont., with a rotation of corn, soybeans, wheat and sugar beets, along with a hog-finishing operation on his farm.
Tyler Vollmershausen, who farms near Innerkip, Ont. Vollmershausen’s preferred rotation is corn, edible beans and a cereal crop. He doesn’t have any livestock on his farm, but is involved in a livestock grazing project with a nearby cow-calf operator.
Michael Schouten, a producer from Richmond, Ont., who grows a corn-soybean rotation and operates a dairy farm as well.
Brian Newcombe, a grower from Port Williams, N.S. He works with two rotations: a five-year grass-alfalfa mix (followed by five years of soybean-corn silage-winter wheat-corn-soybeans) and a grain rotation of corn-soybeans-winter wheat, or corn-corn-soybeans-winter-wheat. His family also milks 70 Holstein cows, and raises 20,000 layer chickens and 120,000 broilers.
CG: At what stage of your rotation do you include cover crops?
For Tyler Vollmershausen and Laurent Van Arkel, it’s all about keeping living roots in the soil at all times. Van Arkel works to establish a cover crop whenever possible. Vollmershausen, however, is more selective with his cover crop options: in 2016, he didn’t want to risk planting a cover crop into drier-than-normal soil. But generally, whenever he’s not growing a cash crop, he’s growing a cover crop. With corn, he spreads cereal rye, and with edible beans, he uses oats, barley and rye.
“In our northern climate and shorter growing season, it can be a real challenge to incorporate covers after all corn, soybean and winter wheat crops,” says Brian Newcombe. “Having winter wheat in the rotation gives us the best opportunity to establish a cover crop early enough in the growing season to produce nitrogen from the legumes for the following corn crop, and to build biomass from the non-legumes to increase soil organic matter.”
Inter-seeding cover crops into corn is a standard for Michael Schouten, although it’s still a work-in-progress with his soybeans, particularly with finding the right timing.
CG: How long have you been using a cover crop in your rotation?
Schouten has been growing cover crops for four years, Newcombe has been experimenting with them for six years, Van Arkel for more than 20 years and Vollmershausen since 2012. Newcombe started under-seeding red clover into his winter wheat fields in spring, then expanded that to three- and four-way mixes into the wheat stubble after harvest. In the past couple of years, he’s tried inter-seeding into standing corn.
Van Arkel started out simply and has expanded his use of multi-blends while Vollmershausen, as he puts it, “really started to get serious” about cover crops in 2012 after years of seeding red clover. He was reluctant to consider it a cover crop since it was seeded only once every three years.
CG: What’s the primary purpose of your cover crop?
Weed suppression tops the list for Vollmershausen, with the goal of matching cover crop selections to the weeds that grow in their fields. “Since we’re not doing the tillage, we’re trying to choke them out,” he says, adding that glyphosate-resistant Canada fleabane is one of many targets. “But it’s also to scavenge nutrients, improve water infiltration, soil health — all of it.”
“All of it” is the same goal for Schouten, although he cites weed suppression as a big plus of cover crops. Erosion control is another goal and ranks at the top of Brian Newcombe’s list. He also echoes the “all of the above” approach cited by the others. “We want to keep our valuable nutrients and organic matter in the field, where the crop can benefit from it, and out of the waterways,” says Newcombe.
Laurent Van Arkel cites three basic reasons for using cover crops, noting that some of them overlap under different applications. One is to improve or maintain soil health, including soil structure and biology. Second is to reduce the impact of wind and water erosion, and the third is to tie up residue fertility, either from manure or that’s left over from the crop.
Asked if there were secondary or other reasons for using cover crops, Schouten says they add organic matter and provide ground cover after corn silage. Newcombe says his long-term goal is to build soil health and organic matter to the point where he can have the soil feed his crops with as little purchased input as possible, so he can get the same yields but capture more profits.
For Van Arkel, cover crops provide added practical and perception benefits. In his multi-blends, he includes flowering species like sunflower and buckwheat to provide late-season food for pollinators. The green fields and flowering plants are an aesthetic benefit that boosts the general perception about farming. He’d also like to see more research, including dollar values on cover crops, to help growers make better-informed decisions.
CG: Did you set out with one goal for your cover crops, and then evolve to another?
“It’s more like I started with one goal of reducing erosion, and I keep adding goals for cover crops to achieve,” says Van Arkel.
Reducing erosion was another of Vollmershausen’s aims in the early going. When he and his father and grandfather were still doing tillage, corn seedlings would get sand-blasted in late-May, so a big goal for them was to reduce the effect in heavier winds. “That led to soil health concerns, and we weren’t really on board with that when we started using rye,” says Vollmershausen. “Then we transitioned away from full-surface tillage when we saw what we could do with the roots.”
For Schouten, adding cover crops came at the same time that he started strip tilling as a means of spreading his dairy manure on a live crop, eliminating any added tillage. “We also wanted to use them for some ‘deep tillage,’” he notes. “It then evolved into all of the other benefits.”
CG: Who or what was the inspiration for using cover crops?
Newcombe makes a point of attending the National No-Till Conference in the U.S. every year, and he finds the speakers and those attending the conferences are sources of great ideas.
Van Arkel meanwhile has been using cover crops since his teen years and says they’ve become part of a soil health system he’s been trying to develop, always moving slowly. “It’s been a 30-year journey that still isn’t complete,” he adds.
For Schouten, it always comes back to strip till as the main inspiration, noting that the two systems work so well together. He moved into strip till as a step towards efficiency and soil health while cover crops complemented and enhanced the soil health aspect.
It was in the spring of 2013 that Vollmershausen was inspired by a presentation by Dr. Jill Clapperton, former AAFC researcher, who spoke on the soil-food web and bio-mimicry, and how to integrate cover crops into the system to emulate nature.
CG: What’s been the biggest challenge with adding cover crops to your rotation?
According to Van Arkel, the challenge has been to develop a system that fits his operation. “There is no cookie-cutter approach to cover crops,” he says. “They need to be tailored to each individual’s operation.
Managing a live cover crop in the spring is the issue for Schouten. “We believe in the benefits of having a living root system in the soil year-round,” he states. “That being said, a living root system is much more difficult to turn into an adequate seed bed. Trying to get out to spray early enough before planting is a challenge (in eastern Ontario) so we’re trying to find that delicate balance where enough of the stand winter kills and the remaining portion is still manageable with the strip tiller.”
A shorter growing season is foremost on Newcombe’s mind. The growing season is far shorter than what he hears from counterparts in the U.S. Midwest. Winter wheat planted after soybeans gives them something green growing in the field for winter and helps with erosion, but it doesn’t produce a lot of biomass in the fall. “However, being in Nova Scotia, surrounded by the ocean on three sides and close to Minas Basin, gives us a little longer frost-free period to help the cover crop grow into the fall.”
The biggest challenge for Vollmershausen has been learning “adaptive management,” a term he picked up from Ray Archuleta, an American soil specialist. “You’re always working with the weather and trying to make good decisions.”
CG: What’s your advice to other growers considering using cover crops?
The comment Brian Newcombe hears most often from growers is that they wish they’d started using cover crops 20 years ago.
In that light, he advises growers to:
- Experiment with varieties, rates and seeding methods to meet your goals for your operation.
- Keep the faith — there are some benefits you aren’t going to see until after one or two years.
- Develop a plan for how and when you’re going to terminate the cover crop for the best planting conditions.
Michael Schouten’s line is always “less is more.”
“You’ll be amazed how low a rate will still give you amazing growth,” Schouten says. But, he also warns, “All of the benefits of the cover crop are negated if you delay any aspect of seedling growth.”
Trying to explain the function of the cover crops is foremost for Tyler Vollmershausen. Once the grower understands those things, he says he sees their interest starting to rise. They need to know, though, that perseverance will be necessary. “It’s too easy to just give up when things aren’t quite going the right way.”
In addition to saying “start slow” and “the benefits are undeniable,” Laurent Van Arkel urges growers to understand the cover crop they’re getting into from the day it’s planted to the day the next crop is planted. “You need to know if the residue will give you problems or if there could be a negative interaction.”
Also a producer needs to know that it takes time and effort to transition into cover crops. As Van Arkel mentioned, there is no “cookie-cutter” approach.
And by all means, says our panel, ask for help. Discuss your ideas with others, and get as much feedback as you can.