By Shannon VanRaes
Farmers hoping to improve germination with vertical tillage may be surprised to learn they might not be using vertical tillage at all, especially if their end goal is black earth.
“The only way you get that is if you actually move or bury the residue, so you can’t have both,” says University of Manitoba soil scientist David Lobb. “You can’t leave the residue on the surface to protect it from wind and water erosion and still expect to get that warming and drying effect. The only way you get that is if you move the residue off the soil.”
Clearing residue from the soil surface is a move away from the conservation tillage method often labelled as vertical tillage, he explains.
The issue lies less with how vertical tillage is defined and marketed, says Lobb, adding that vertical tillage is essentially a rebrand of a conservation tillage tool developed in the early 1980s.
According to Lobb, the idea isn’t new, but rather it’s a fresh face to a decades-old idea related to conservation tillage.
“Those types of tools have existed since 1980 … and those implements were designed, as they still are, on conservation tillage equipment, they are designed to cut residue and disturb the soil without moving it or particularly inverting it,” he says.
If a vertical tillage unit is leaving the soil surface black, which can increase soil temperature and speed up the germination process, it doesn’t fit the definition of the original conservation unit touted as vertical tillage roughly 10 years ago, Lobb says.
Most units bearing the vertical tillage moniker include the rippled, waved or bubbled coulters that till the soil without inverting it, loosening up the growing medium, while chopping through problematic residue. However, these implements won’t leave the soil black, says Lobb, adding that the implements are being modified and have the potential to cause lots of disturbance, throwing as much soil as a tandem disc, especially if operated at higher speeds.
“If your goal is to warm up and dry the soil, then you need to get some soil on the surface and you need to bury some residue,” says Lobb. “So if that’s the case then you don’t need vertical tillage and you can just go back to a tandem disc.”
Landon Friesen is conducting his own experiment when it comes to what tillage method is best for his farm near Crystal City, Man. and that includes looking at germination. However, the results won’t be in for some time yet.
“It’s been so cold here the seed hasn’t come out of the ground, but I’m sure if you ask me again in a week or two I can give you a better answer, because we did lots of strips between vertical till and conventional tillage side by side this year to see if we could see something,” says Friesen, who is currently renting a vertical tillage implement for the few acres he’s using it on.
“I don’t want to use it blindly,” he says. “They’re not cheap, so I’m not going to go out and buy a $175,000 tool that might not do any better of a job than what I have. I’m all about making sure things are going to pay back and that things are worth it.”
He hopes the results of this year’s side-by-side trial will help him make decisions about what tillage to use going forward.
“We’re a conventional tillage operation that is doing less and less of it all the time … so we thought, let’s try vertical tillage and incorporate a little bit of dirt with the residue and chop the residue,” says Friesen. “And we’re quite happy with the results; the drill goes into it very nicely and we didn’t have to crack open the ground and dry it out, so for us that was a win.”
One province over, Cynthia Wesselingh is using vertical tillage to break up old hay land on her farm near Saskatoon, Sask.
“Before we had a vertical tillage machine, whenever we broke up hay land, we used a really heavy disc, usually a big heavy tandem disk, and to get those to work in our experience … you had to go quite deep in these old hay pieces,” she says. Even then, the results weren’t great.
“It would take four to five years to get those disc undulations out of the field,” says Wesselingh.
The unit goes beyond the design of a traditional conservation or vertical tillage implement, including a rolling basket-style geo-packer. The results go further than just incorporating a little trash to bring old sloughs and hay land back to black earth, which does have a marginal effect on germination, according to Wesselingh.
“It may germinate a hair quicker, but the catch-22 is that it is black so it will dry out faster,” she says, adding that the black earth can also create the optical illusion of quicker germination. “With it being black you’ll see the rows faster.”
Like Friesen, Wesselingh also began by renting a vertical tillage implement before making the plunge and purchasing one.
“We were unsure how it would work when we first got it, but for us it’s done a tremendous job; it’s just eliminating the back-bouncing, tractor-bouncing work of having to disc it so heavily,” she says. “Overall, we’re pretty happy with it. It’s the one machine in our operation that’s able to do a lot of different stuff for us.”
Lobb says rather than focus on what a tillage implement is called, farmers should focus on what the implement does and if that action is right for their farm.
“The farmer needs to ask themselves why they’re doing the operation; what they’re trying to achieve,” says Lobb.
If a farmer is trying to achieve better germination, a tillage unit that throws soil then compacts it with a rolling basket might be the way to achieve that goal. However, Lobb cautions better germination can come with the trade-off of tillage erosion.
“They call them finishing tools, but when they operate at high speeds, they throw soil, they drag soil, they will actually create a lot of disturbance,” says the soil researcher. “Essentially, you’re doing one tillage pass … disturbing the soil so that it will warm up and dry out, and essentially packing the soil after with a rolling basket, you’re trying to level it off and pack it down. Well, that means you will have better germination because you have a better seed bed to plant the seed into.
“So that will give you better germination, but again it has nothing to do with vertical tillage per se. It has to do with tillage,” says Lobb.
Friesen also notes the wide array of implements and tools labelled as vertical tillage can be confusing.
“I think you’ve got vertical tillage, which is straight disc in the ground with maybe a harrow and a rolling basket, then you’ve got these high-speed discs that are a glorified double disc that move a lot of dirt and use a lot of horsepower,” he says. “Everyone has got skin in the game, so it’s just a matter of finding one with parts availability that works for you.”
