Blending scores big with cover crops — and diversity

More growers are exploring more blends with specific goals in sight

At Canada’s Outdoor Farm Show this past fall, the cover-crop focus was on diversity. There was a high-diversity blend, a six-way blend, a Merlin (Ontario) Multi-Mix and a soil-building mix. There was even a cool-season N-fixing blend, just to gauge its potential.

If it seems like a lot to take in, get used to it. Cover crops are getting more sophisticated.

According to Anne Verhallen, soil management specialist in horticultural crops with the Ontario Ministry of Agriculture, Food and Rural Affairs (OMAFRA), the high-diversity blend alone contains 16 to 20 different seeds and can cost more than $50 per acre.

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With so many options and so many purposes, the first question she asks a grower is: “What is it you want to accomplish with a cover crop?”

“I’m definitely seeing more interest; I think I’m seeing more acres, and sizeable acres at that,” says Verhallen, adding there are producers who always plant cover crops and who will continue to do so. “They’re often the guys that are on the light, sandy soils or those who have early harvested crops and they know they need to do that to maintain their soils.”

But Verhallen is also driving past fields that have never had a cover crop in the past, yet were in full green at some point in 2015.

There are other reasons why growers gravitate towards cover crops, and Verhallen cites 2012, which was a dry year, that sparked an increased interest in covers in part because so many livestock producers were short on feed. Last fall there were still a lot of cover crops out there, most of which had not been taken as feed. In some areas, however, covers had been plowed down, and that’s not something Verhallen likes to see.

When farmers invariably come asking, she responds with several different questions of her own, because, as most agronomists, advisers and dealers will agree, the diversity across the farming spectrum is too great for pat answers.

Before she can provide a grower with more information on cover crops and blends, Verhallen needs to know the cropping practices, rotations, soil types, farm location, past crops and what’s coming after the cover crop. And those are just part of the introduction. A grower also has to define what he or she is trying to get out of a cover crop. Is it to keep the soil covered and the soil life active after wheat? Is it part of an IPM process to improve and maintain soil health? Is there a short-term remedial need to break up compaction?

Similar to no till, yet different

Whether it’s red clover, an oat-radish combination or a diverse blend, the task of winning over growers to cover crops is similar to selling growers on no-till or reduced-till management. Yet it’s also different because some of the drive in working with cover crops is coming from no-tillers or reduced-till growers.

“They find they need ‘something else’ to keep the biology moving along, and no till hasn’t quite got their soil to the levels they wanted it to reach,” says Verhallen. “And then some people have bought in on the whole ‘more roots, more diversity, more biology’ approach, and seeing that that’s an opportunity for them to harvest the sun and the carbon and put it back in the ground. I really try to sell it as part of a system, and that it’s generally not going to change things in a year or two.”

Adding more diverse blends of cover crops means more opportunity to address a variety of soil maintenance issues.

Adding more diverse blends of cover crops means more opportunity to address a variety of soil maintenance issues.
photo: Blake Vince

Some have told her that they’ve raised their soil organic matter by significant amounts in a relatively short period of time. But Verhallen is quick to remind growers that it can take a decade or more to raise soil organic matter on heavier soils. If a grower is seeing that quick a change, it might be due to sampling or testing discrepancies, or badly degraded soils.

The good news is that they’re growing cover crops, which means they’ve made the choice to commit to a higher management mindset, and getting started is often the biggest challenge. Some people have a problem with the labour and the time, while others resist due to the seed costs or availability. And others view it as a risk.

“Overall in the system, it’s going to reduce your risk and build a more resilient soil, but on a year-by-year basis, it requires more management, and depending on the year, it may actually increase some of your risk,” says Verhallen. “The mindset is definitely similar to no till —it’s labour, time, dollars, ‘bother’ and risk — and they have to want to do it. With cover crops, you tend to dance in and out of it according to the season and as your time allows you to do it, but if you want to see the benefits from it, it has to be incorporated as part of the system.”

It’s maintenance, not magic

One lesson that Verhallen loves to share on breaking down barriers with cover crops comes from Odette Menard, an agricultural engineer and soil specialist with the Ministry of Agriculture, Fisheries and Food in Quebec (MAPAQ). Soils, says Menard, are not like a tractor. A grower performs maintenance on a tractor —changes the oil, replaces worn tires — to keep it operating efficiently. But that maintenance doesn’t improve yields, and that is not the case for soil. Cover crops are part of a soil maintenance system, he says. They’re part of a mindset and a whole systems approach.

Digging in to have a quick look at the health of the soil.

Digging in to have a quick look at the health of the soil.
photo: Blake Vince

It’s that same approach that applies to diverse blends of cover crops, especially with the more complex or with more legumes in the mix. With rye, clover, radish or oats, supply or pricing usually aren’t an issue. It’s with the addition of more legumes, like peas or vetch, and some of the different clovers that the costs can add up quickly. Then there are the mixes that include flax, phacelia, sunflower or safflower, which can become expensive and a bit more challenging to source.

Phacelia has grown in its popularity recently, says Verhallen, which means it’s easier to find, but only if you don’t wait too long in a season. Flax is less expensive than some might realize, and its smaller seed size makes it more cost-effective. The same can be said about sunflower, where its larger seed size means a little goes a long way.

“It’s a cover crop!”

Blake Vince is one of those growers who has adopted the “whole process system” approach to cover crops. It was in 2011, following a meeting with Ohio-based farmer Dave Brandt and learning how he uses oats, radish and peas that Vince decided to use cover crops on his own farm. He began with canola, wheat, radish and some leftover soybean seed, just to see how it would perform on his fields. At the time, he had different comments concerning what most believed was a winter wheat crop, noting it looked great in the fall, poor in the spring but a lot better as he was preparing to plant his corn. His response to each comment was the same: “It’s a cover crop.”

Today, he’s noticed a definite uptick in the interest in cover crops, and not just simple covers but complex blends. Just as Verhallen has fielded different questions, Vince has heard different concerns and goals voiced.

One of the many cover crop blends showcased at Canada’s Outdoor Farm Show in 2015.

One of the many cover crop blends showcased at Canada’s Outdoor Farm Show in 2015.
photo: Blake Vince

“Guys are starting to pay attention where they’re in a two-crop rotation and they’re seeing a yield drag, and they know that the economics aren’t there for wheat,” says Vince, who farms near Merlin, Ont., southwest of Chatham. “Some are starting to experiment with inter-seeding cover crops with their corn, and I’m starting to see guys experiment with fall-planted cereal rye, and those things are starting to get a bit of a toe-hold, although they’re a long ways from common practice.”

Vince echoes Verhallen’s paralleling of diverse blends and cover crops in general to no-till management. It’s not done with a short-term focus, and it requires a mindset which envisions success, not an attitude that surrenders when the going gets tough.

“We shouldn’t have to worry about experimentation with cover crops,” says Vince. “With no till, there was a cause-and-effect associated with it, we needed to put the seed in, we needed to make sure the seed was going to grow because we needed to harvest a crop at the end of the year. With cover crops, we should be doing it for a multitude of reasons, one of which, primarily, is its soil-building ability. The benefit is not immediate, and unfortunately that’s what happens with most acquisitions at the farm — with a short-term solution to a problem of some description.”

With cover crops, he adds, you’re buying into things for a net benefit that may not show up for three or five years, whether it’s a subtle increase in production or as a return on investment in the form of an improved quality of products that leave the farm and benefit society. Vince also uses cover crops to reduce his consumption of inputs, whether they’re fertilizers — and the legumes in his mix will release supplemental nitrogen — or cereal rye that has an allelopathic compound to suppress or reduce weeds.

“But most times, I’m looking at it as a long-term capital improvement strategy for my farm, much like tile drainage,” Vince says. “In today’s agriculture unfortunately, one of the last things a farmer has ultimate control over is how he or she chooses to manage their soil. Everything else is pretty much dictated to them, whether that’s the price of inputs or the commodity market we play in.”

Not a piece of cake

When asked to describe the “Merlin Mix” showcased at the Outdoor Farm Show in 2015, Vince emphasizes that it isn’t a time-honoured recipe that stays the same year after year like a cake at a church bake sale. It’s a product of evolution, he says, a combination to which he’ll add or delete a species, simply by what he sees working on his farm from one year to the next.

In general, Vince works with six legumes for the purpose of building nitrogen and three or four grasses (corn, oats, cereal rye and volunteer winter wheat coming from behind the combine). Then he’ll try flax, sunflower, phacelia, and those are great for pollinators, along with the black residue they leave behind as they decay courtesy of solid tap roots. Finally, those plants have an aesthetic value, helping in some regard to create awareness by drawing attention to their growth.

“It makes people sit up and realize that as a farmer, I care about my environment,” says Vince. “I’m doing something proactively not only for my betterment, but with the ideal that farmers as a whole are invested in everyone else’s well-being.”

He’s even tried fababeans and sunn hemp, although the latter doesn’t hold much promise since it has to be planted before June 21. He’s also worked with millets and other grasses that he’s planted later in the season.

“I have an Excel spreadsheet and I create my own recipe on an annual basis based on availability of seed, and that gets to be a challenge as the popularity of cover crops grows and expands,” says Vince. “Some things come and go out of the mix because I can’t get my hands on the seed or I can’t get as much seed as I want. When you think of the seed types and shapes, there’s a range of seeds that are large, like a fababean, down to a forage kale which is the size of the tip of a ballpoint pen or phacelia, which is like iron filings. It’s all about creating this ratio.”

Where sourcing the various seeds can be a challenge, Vince’s spreadsheet helps in mapping but also with the economics of his particular mixes. The spreadsheet function can calculate the cost per pound and seeds per pound needed for his blends.

Vince also credits his diverse mixes for a return of wildlife to his farm. Bobolinks, declared an endangered species in the past 10 years, now nest in his grasslands and there’s anecdotal evidence that deer have been frequenting his cover crops (signs of them chewing on radish and other plants).

“I know that through my careful reduction of costs and capital expenditures, that’s what’s allowing me to remain viable for the long term,” says Vince. “The key thing in all of this is to think differently, and think of it as an opportunity to learn and that we don’t need to be so precise. We can observe changes that occur in our soil, and the best tools for that job are our legs and a shovel, our eyes and our nose. And really, most farmers already have the tools to get started, so it doesn’t require additional capital assets, they just need the aptitude and the attitude to implement it.”

This article was originally published in the February 2016 issue of the Soybean Guide

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Ralph Pearce

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