It’s an established fact that seeding depth and plant spacing are critical factors in maximizing yields and uniformity in some crops. That’s why corn and soybeans are planted with planters designed to singulate each seed and place it at a precise depth.
Wheat isn’t generally seeded with a planter, but as part of this Wheat School video, we visit a research trial in southern Manitoba looking at how a popular Canadian Western Red Spring (CWRS) wheat variety responds to the singulation and depth control of a planter.
“Anytime we’re using a planter it’s all about getting better seed placement. If you compare a planter to an air drill, with the air delivery system we can have inconsistency due to seed bounce, because there’s a lot of air being forced through the system to push the seed, whereas with the planter, the seed is gravity fed,” explains Brunel Sabourin of Antara Agronomy, based at St. Jean, Man. (continues below)
The trial compares four replicated treatments, all seeded with the same CWRS variety, targeting a depth of 2″, and the following seeding rates and row spacing:
- Air coulter drill — 1.2 million seeds/ac (around 1.6 bu/ac) on 10″ row spacing
- Planter, low rate — 600,000 seeds/ac on 15″ row spacing
- Planter, medium rate — 900,000 seeds/ac on 15″ row spacing
- Planter, high rate — 1.2 million seeds/ac on 15″ row spacing
“We’re more evaluating just how the wheat reacts to the singulation, not what the optimal row spacing is for the wheat,” says Sabourin, noting narrower row spacing would be ideal for maximizing yields — farmers in high-yielding areas in Europe will plant wheat on 4″ or 6″ rows.
— Antara Agronomy (@antaraag) May 15, 2018
The planter’s depth control has already shown to result in more uniform emergence — a benefit that might be less noticeable if it weren’t for dry conditions this spring, he notes. “With the drill we were getting as much as half an inch to three quarters of an inch differences in seeding depths, so that helps explain why we only see half of it emerged so far. One good rain would fix that.”
They’re also going to be paying close attention to any differences in the number of tillers, the number of heads, the size of the heads, and the uniformity of the plants in each treatment.
Since most wheat varieties in Western Canada tend to have quite a few tillers, he says future research could compare how different varieties respond to the depth control and singulation of a planter, which could provide insight into ways to implement variable seeding rates and other precision tools for boosting wheat yields and efficiency.