Is your canola field fit for straight cutting?

For immediate release 

August 19, 2008: So you want to straight cut canola this fall. The potential benefits are great: fuel savings, time savings, improved yield and seed quality. But do not pass go until you have assessed each canola field for the following four factors, says Dave Vanthuyne, agronomy specialist for the Canola Council of Canada.

The Four Fit Factors 

Crop canopy – The crop should be well knitted and slightly lodged to reduce potential seed loss through pod drop and shelling. Frost, drought and insect damage all affect pod integrity. A uniform crop with minimal green weed growth is also a huge advantage when straight cutting.

Disease – The crop should be relatively free from blackleg, fusarium wilt, sclerotinia and alternaria, as these diseases can cause premature ripening, which makes the crop prone to pod shatter.

Hail – Crops affected by hail are poor candidates for straight cutting because they typically see greater disease infection due to tissue damage. The physical damage also reduces pod integrity. If late season hail is common in your area, keep in mind that hail will cause more damage to a standing crop than a swathed crop.

Frost risk – Canola seed is at significant risk for fall frost damage until seed moisture drops below 20%. This moisture drop will take much longer in a standing crop, making late maturing crops poor candidates for straight cutting. Canola will be much more vulnerable to yield loss and downgrading from frost damage when standing.

“It’s all about minimizing losses due to pod drop and shatter,” explains Vanthuyne. “Anything that may have weakened the pods or petioles makes a canola crop a worse candidate for straight cutting.”

Time application of pre-harvest glyphosate to glyphosate-tolerant varieties to assist in the dry down of green weeds and control perennial weeds, but remember that this will not hasten crop dry down.

For non-glyphosate-tolerant varieties, it’s critical not to apply the herbicide too early, warns Vanthuyne. Apply when the crop has 30% or less seed moisture content. At this stage – past typical swathing timing – most seeds will have turned brown or black.

You can also use a desiccant, but be very careful with timing. Delay application to allow seeds to reach physiological maturity when an average of 65-75% of the seed (on the whole plant) has turned brown. This is well past 75% seed colour change on the main stem. Dry down will be very rapid so be ready to harvest shortly after a desiccant application to minimize pod drop and shatter, says Vanthuyne. 2

When the combine hits the canola 

“I always counsel patience to growers who are straight cutting canola,” says Vanthuyne. “You usually have to delay straight cutting at least two weeks past when you would swath and combine a canola crop, in order to get the proper seed moisture content.”

When out in the field keep reel speed and ground speed evenly matched and consider cutting at an angle to the direction of lodging to minimize shelling losses that are caused by the header, he adds.

Straight cutting canola at seed moisture above 10% should help reduce losses from shelling and pod drop. But appropriate bin space with aeration and/or drying capacity is a MUST because safe storage will be an issue with a higher seed moisture content coming off the field.

To learn more about straight combining, go to the Canola Growers Manual online:

For more information, contact:

David Vanthuyne, Eastern Saskatchewan, 306-946-3588, or 

Kelly Funke, Communications Officer, 204-982-2111 

For more information in your area, contact:

Derwyn Hammond, Agronomy Specialist, Manitoba Region, 204-729-9011 

Doug Moisey, East Central Alberta and Northwestern Saskatchewan, 780-645-3624 

Matthew Stanford, Southern Alberta and Southwestern Saskatchewan, 403-327-4832 

John Mayko, West Central Alberta, 780-764-2593 

Erin Brock, Peace Region, 780-568-3326 

This media release is supported regionally by:

Alberta Canola Producers Commission; Saskatchewan Canola Development Commission; Manitoba Canola Growers Association; Canola Council of Canada; Peace River Agriculture Development Fund; B.C. Ministry of Agriculture & Lands.