Caution Needed When Storing Canola

WINNIPEG - Sep 19/07 - SNS -- Canada's canola growers need to exercise caution when storing canola this year because of the variable weather conditions experienced during harvest.

Canola Council agronomy specialist David Vanthuyne says growers need make sure they first condition canola to storage-safe temperature and moisture levels.

Conditioning involves moving air through the grain mass to prevent spoilage that results from moisture migration and seed respiration. Canola harvested much above 8 to 9% moisture must be conditioned, especially if grain temperatures are above 25º C.

Vanthuyne also stresses that growers must regularly monitor their bins for heating or mould growth. Because farmers are using bigger and bigger bins, more heat can be generated and/or trapped in the bin. Even dry canola can still be at risk if it has a high temperature, especially if parts of the bin contain green material which can be potential spots to start the spoiling process, warns Vanthuyne.

He explains that the objective is to cool the seed below 15º C and lower its moisture content to 8% moisture. "Aeration and/or 'turning' the canola can be an effective way to avoid spoilage," Vanthuyne says, "but if moisture levels are above 10% to 12%, growers need to consider heated air drying."

Recent cooler temperatures may give growers a little more time to condition canola, but Vanthuyne warns that growers must not assume that nothing can happen "even if the stored canola is already down below 15º C". Pockets of damp seed or green dockage can create hot spots that can quickly spoil a bin. Once again, he says proper conditioning and monitoring are the solution.

Vanthuyne adds that growers can't drop their vigil once they've conditioned canola. Freshly harvested canola can maintain a high respiration rate for up to six weeks before becoming dormant. Over time, the seed may become mouldy or heat damaged, and in severe cases it can ignite. This sweating stage is a very unstable condition for binned canola.

Vanthuyne reminds growers to monitor the binned crop all season long.. "Monitoring is a 'best practice' just like keeping malathion far away from stored canola", he adds.