Canola can yield better when swathed later

Summary results pooled for both 3 and 5 lb/ac seeding rates at all locations based on similar trends observed. Straight cut treatments at 10 of 12 locations produced relative yield of 107% vs 30-40% SCC.

Canola yield continues to increase with later swathing — to a point. At 50-60% seed colour change on the main stem, yield plateaus and stays at around the same level all the way through to straight combining. Some of the earliest pods may shell out with later swathing, but improved size and maturity for seeds in later pods makes up for this. Delaying swathing while you wait for more plants to mature is generally positive for yield, unless soil moisture is inadequate to fill green seeds, or unless a season ending frost or snow could happen at any day.

Early shelling may also be a bonus if pods are shelling because they’re diseased and contain peppery seed that won’t amount to anything.

If good seed is at risk of shelling out, consider swathing in the evening or morning when conditions are cooler and plants are dew-covered. This will reduce the risk of shattering.

Uneven crops make for a tough swathing decision. Swathing at the right time for the majority of plants is the best you can do. The ideal is to wait until the latest seeds are firm when rolled between thumb and finger.

August podcasts on swathing timing:

Murray Hartman, Alberta Agriculture canola specialist

Troy Prosofsky, CCC agronomy specialist