Canola: Straight cut versus swathed

New shatter-resistant canola varieties have a straight cutting edge

ripe canola at sunset, Glen Nicoll

After 20 years of straight cutting canola on his central Alberta farm Wilson Lovell doesn’t even own a swather anymore, although he admits waiting for the crop to ripen is hard on his finger nails.

He’s evaluated the two harvest options closely, and Lovell is convinced there is risk of a 10 to 30 per cent yield loss from swathed canola on his farm near Clive, northeast of Red Deer. And he’s done a lot of hands-and-knees field inspections to determine that losses appear negligible when straight cutting. Even after having standing canola buffeted by exceptional winds in 2015, he still binned a 59 bushel crop.

“I think the pro of straight cutting canola is that you will harvest more crop,” says Lovell. “And on the con side, well it is really hard on your nerves. I haven’t swathed for more than 20 years, but it’s still hard waiting for the crop to mature.”

On the flip side, Kevin Serfas west of Lethbridge in southern Alberta is committed to swathing canola. With a lot of acres to cover with 16 combines in a three-month harvest window he says it slows him down to wait for standing canola to ripen.

“Swathing canola gives us a 10 day head start on the overall harvest season,” says Serfas who is part of the family owned Serfas Farms Ltd. “We plan on one combine doing 3,500 acres. If we went to straight combining we’d need one combine for every 2,500 acres.” He figures with often strong prevailing westerly winds yield losses would be higher if the crop was left standing. He doesn’t rule out one day switching to straight cut canola, but for now he’s sticking “with a system that works best for him.”

  • Read more: Five reasons to hold off on swathing canola

The system that works for Wilson Lovell is to grow leading hybrid canola varieties — he works with different herbicide tolerant programs — and use proper agronomics to produce a good canola stand. “The wheat is always harvested first, but we keep an eye on the canola,” says Lovell. He waits for a killing frost before combining the oil seed.

“The crop can be fully mature, with 20 per cent moisture, so we let it stand. As soon as we have a couple nights of -10 C temperatures I know the moisture is gone and then we combine canola.”

Straight cutting research

Is one harvest approach better? Nathan Gregg, a project manager at the Saskatchewan-based PAMI (Prairie Agricultural Machinery Institute), says that really isn’t a question he’s trying to answer in a three-year research project comparing straight cutting and swathed canola harvest system. He’s just looking for yield differences.

So what has he learned after two years?

“It doesn’t matter what you are combining and whether it is straight cutting or swathing canola or any crop, you’re going to have losses,” says Gregg. “If you ask farmers about harvest losses most will estimate one to two bushels per acre as the most common answer. But we found when you actually measure it, it is more commonly in the two to five bushel range. And depending on the situation we have seen losses as high as 10 bushels per acre. And it’s not always easy to see.”

Wind and wildlife activity are obvious causes of harvest loss, but travelling too fast with a combine is a leading factor. “We recommend travelling at three miles per hour and many farmers say they can’t afford to go that slow,” he says. “They might want to consider a second combine, and run both a bit slower.” While renting or leasing a second combine might be viewed as an added cost, he recommends pencilling it out compared to potential losses.

And he points out that all makes of combines have “leakage” — either at the cutting and gathering points at the front of the machine, or at the threshing and chaff collection and distribution points at the back of the machine.

Periodically collect and check what is being kicked out the back of the machine. Collect the straw and chaff from the full width of the back of a combine, get rid of the bulky material and actually count how many seeds are passing through.

In two years of a three-year project on average the swathed canola has produced about four to five more bushels per acre than straight cut canola. These are all common hybrid canola varieties. But, there is a but.

Improved shatter resistance

Most of PAMI’s research involved established hybrid varieties, but they also looked at a new hybrid from Bayer Crop Science L140P, which was developed with improved shatter resistance for farmers considering straight cutting. In the PAMI project straight cutting L140P allowed them to harvest three to four more bushels per acre over swathed and combined canola.

On the equipment side they are comparing draper headers, to rigid auger headers, to Varifeed headers. There wasn’t a huge difference between any of the systems, however if Gregg had to make a call, it appeared the rigid header had the most losses when straight cutting standing canola and the Varifeed system, which can get the cutter bar up to two feet out in front of the reel, had the least losses. Again, not a huge difference.

The PAMI research continues through 2016.

About the author

Field Editor

Lee Hart

Lee Hart is editor of Cattleman’s Corner based in Calgary.



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