Twenty years ago, rocks, clods and root balls were a frustrating and unavoidable part of soybean production. Today, somewhere in the range of 90 per cent of Canadian Prairie soybean growers depend on land rollers — a low-tech but highly effective technology — to smooth their land, improve crop emergence speed and uniformity, preserve their combines at harvest, improve yield potential, and more.
Now, producers are increasingly rolling these long drums into other crops, and finding additional uses and benefits along the way. “Of course I use a land roller — doesn’t everyone?” asks Dale Crowle, who farms near Hanna, Alta.
Why it matters: You don’t have to grow soybeans or have rocks in your fields to benefit from using a land roller — faster emergence, better uniformity, increased seed-to-soil contact, erosion prevention, and improved residue management and crop cleanliness are just a few additional advantages.
In fact, no. Use of the technology varies regionally and by crop. While Crowle is right that the vast majority of farmers in central Alberta — despite not growing soybeans — do roll their land, rolling is much less common in more northern growing regions of the Prairies.
“Land rolling started out as primarily rolling for rocks in crops like soybeans that grow close to the ground. But, over the years, it’s transitioned to people seeing the benefits of rolling for multiple reasons, even if they don’t have rocks, and even if they aren’t growing soybeans,” says Bruce Johnson, director of innovation at Summers Manufacturing.
Most land rolling occurs shortly after seeding in order to smooth the field and increase seed-to-soil contact. “The farmers we work with have reported they get a two- to three-day faster emergence in fields they’ve rolled, and better uniformity at emergence. They tell us it compensates if their planter isn’t perfect,” says Johnson.
Some producers land roll after emergence to increase the top-end potential of their crop. Rolling post-emergence is most common in soybeans and is typically done at the V1 to V2 stage. Currently, several university research studies are underway to determine exactly what causes yield potential to increase in soybeans from post-emergence rolling.
Stressing the plant via rolling does cause a soybean plant to branch out and produce more pods. However, it’s still uncertain whether additional yield comes from these extra pods filling, or whether the yield actually results from a combine’s header being able to run closer to the ground, leaving fewer pods in the field.
Wheat and corn crops
Crowle rolls his wheat and corn crops after emergence in order to smooth field inconsistencies. “We roll our hard red spring wheat when it’s five, six inches high. We’ve done it a lot, especially in the last couple of years — and had no issues. It pushes down the rocks and levels off the mole hills, which we have a lot of out here. It also helps deal with erosion in some of the areas with heavier soil.”
Though Crowle knows rolling right after seeding could improve emergence uniformity and speed, the timing has never worked out for him to manage an early rolling. Also, he’s seen the potential downside of over-rolling a newly seeded field, and it makes him nervous.
“One of my neighbours did some corn and their land blew this year. They busted it up too fine and we had a dry spring, so their land blew badly,” he says. “For me, my priority is knocking down the rocks and mole hills, and that works fine after the crop is already up.”
Note that farmers who want to roll post-seeding, but are particularly concerned about wind erosion, sometimes choose a coil packer instead, which creates a herringbone pattern rather than a smooth surface on the ground, reducing wind and water erosion.
Less wear and tear on combines
Dealing with root balls, rocks and residue early in the season means less wear and tear on combines at harvest. The header can skim the ground without damage and the combine’s inner workings aren’t ground down by nearly as much dirt moving through the machine.
“We call land rollers a combine’s best friend,” says Johnson. “If you see a combine harvesting soybeans in a field that has been rolled, the dust cloud behind the combine will be brown because most of what’s blowing is chaff. If you see a combine harvesting soybeans in a field that hasn’t been rolled, that dust cloud will be black with the dirt that’s travelled through the machine. Given how abrasive dirt is, the more dirt you can keep out of the machine, the better off your machine will be in the long run.”
Crop processors have clearly taken note of land rollers’ impact on crop cleanliness. Some bean companies now offer contracts that either include a premium on fields that are rolled or a discount on fields that are not rolled due to the difference in the amount of dirt in the beans.
In minimum and zero till operations, land rolling can also be an effective residue management tool, especially for hardy stalks like sunflowers.
Land rollers, which vary in rolling drum length from about 15 to 90-plus feet, crush clods and push down rocks, yet cause surprisingly minimal compaction.
“Compaction is a very legitimate concern,” says Johnson. “I can show you the calculations — when you spread the weight of the drum across the whole roller, it’s actually less compaction than the footstep of an average person.”
Summers Manufacturing was one of the early manufacturers of land rollers, introducing its first model in 2005. Though the basic design hasn’t changed much since then, the company has innovated as producers’ needs change, such as building bigger rollers, improving the ease of folding for transport and beefing up wheels.
“We’ve also upgraded our rollers so they’re well set up for a lot of highway miles. It used to be that a farmer could drive to most of their farmland in 20 minutes. Now, a lot of farms are spread out over a large area. So, we’ve built land rollers with heavy-duty transport for all those road miles,” says Johnson.
“It’s a pretty simple piece of equipment, but we put a lot of thought into it. The tubes need to be perfectly round and balanced; the shaft perfectly centred. By being very diligent about our process, you get equipment longevity.”