Swathing when hot can lock in green

August 31, 2011 - Issue 22

Harvest

With day time highs in the 30s or high 20s, growers should wait for cooler days before swathing the crop, if possible. Cutting canola in hot conditions will lead to rapid dry down and desiccation. Chlorophyll may not have time to clear from immature seed, which locks in high green counts.

If growers feel they must swath, wait until temperatures cool down in the evening and then swath at night to take advantage of those cooler temperatures and any moisture from dew. The goal is to minimize the initial temperatures and maximize the initial moisture levels within the swath, to delay desiccation of the plants in the swath and allow as much initial curing as possible.

Swathing on hot days is especially risky for canola crops with low levels of seed color change. Swathing canola prematurely in hot, dry weather is a bad combination, causing the highest yield and quality losses.

Got green seed? Growers waiting for green to clear before combining swathed crop may want to call their delivery point. If green is down below 5%, taking the price discount on offer may be better than leaving crop in the field, especially if the swath is ripe, light and at risk of significant wind losses.

Canola Watch