Canola seed’s small size makes it sensitive to deep seeding. Both uniform placement and depth tend to improve emergence and seedling survival rates, which is crucial considering the high cost of seed. It’s not just about seed cost, though. It’s about creating a better environment to produce a stronger crop.
Swedish machinery manufacturer Väderstad believes singulation provided by its PowerShoot technology could be the solution that significantly improves canola establishment in Western Canada.
Canola Council of Canada (CCC) recommends a plant stand of five to eight plants per square foot. How those plants are spaced, though, makes all the difference. When seed is planted too close together the emerging plants compete for resources. Broadcasting seed onto the soil’s surface is unreliable as it can impact seed to soil contact and often leaves seed without adequate moisture. If incorporated, seeding depth is, more often than not, inconsistent.
Canola seed is also sensitive to seed-placed fertilizer, particularly nitrogen and sulphur. According to CCC, safe rates of seed-placed nitrogen may be as low as 10 pounds per acre. This, however, depends on row spacing, seed and fertilizer separation in the row, soil moisture conditions and soil type. In a nutshell, precision pays and singulation helps achieve this more accurately.
Väderstad believes its Tempo L-series planter could be a good solution.
There’s huge potential for improving canola establishment, says Clas Asknert, Väderstad area sales manager for Western Canada. “Instead of having a controlled spill of canola seeds in the row, we can actually singulate them,” he said.
Tempo L is a trailed high-speed, high-capacity planter, available with 8, 10, 12, 16, 18 or 24 row units. Its PowerShoot technology further ensures precision.
On traditional planters, where seed falls freely through the seed tube from the seed meter to the soil, vibration causes seed to bounce, which reduces accuracy as planter speed increases. Additionally, air drill metering systems release multiple seeds at a time, which creates further variability in the plant stand. And while air drill metering accuracy has improved, it is still not as accurate as planter singulation.
Tempo’s seed metering discs use pressurized air in the chamber to release one seed at a time, explains Kris Cherewyk, a Saskatchewan-based Väderstad agronomist. This same air pressure shoots the seed straight down the seed tube.
“Using pressurized air eliminates the gravity component where the seed can bounce off the sides of the tube and create placement variability,” he says. “A rubber stop wheel brings the seed to a halt firmly in the soil instead of bouncing off the sides of the seed trench, providing accurate placement in the row.”
Tempo’s seeding rate is calibrated in seeds per acre as opposed to air drills, which are calibrated in pounds per acre.
“The seeding rate conversation needs to be shifted away from what growers have traditionally referred to as their seeding rate, pounds per acre, to seeds and plants per square foot,” says Cherewyk.
“Determining seeding rate at pounds per acre depends greatly on a seed lot’s thousand kernel weight (TKW),” he adds. “When growers base their rate on a set pounds per acre, they open themselves to discrepancy in the actual amount of seeds being metered out as TKW can vary from one seed lot to another.”
In 2019 alone, Cherewyk saw TKW numbers vary anywhere from 4.0 grams to 6.9 grams. This is quite substantial, he says.
“For comparison, if a grower’s target seeding rate is six seeds per square foot, a seed lot of 4.5 grams TKW is 2.59 pounds per acre, while a seed lot of 6.5 grams TKW is 4.05 pounds per acre,” says Cherewyk. “Therefore, the idea of basing a seeding rate on a set pounds per acre is no longer relevant when discussing accurate plant stand.”
This shift in conversation should come as no surprise. BASF recently started selling canola seed by number of seeds per bag instead of pounds. Growers can now select between four different weights.
Another important factor to consider when determining a seeding rate, says Cherewyk, is seedling mortality. Typically, mortality rates when planting canola with a Tempo range from 15 to 25 per cent, he says.
“Growers do need to be mindful of the conditions they are seeding into. A lower canola plant stand further emphasizes the need for effective weed control, insect control, residue management and good fertility and soil health, which should be a priority on every farm as part of a sustainable agronomy plan,” says Cherewyk.
“Canola is a resilient plant, and given the space it requires, it will produce a bountiful crop to maximize the most return on investment possible.”