Check condition of stored canola now – with caution! (April 13, 2006)

April 13, 2006: Canola growers should be checking their bins right now for signs of possible seed deterioration but Canola Council agronomists are advising special caution this year. Some binned canola is extremely hot this spring and could even catch on fire.


Canola Council agronomist David Vanthuyne says he’s had a number of reports of canola spoilage in the bin over the past few weeks, including a couple of isolated cases where seed has actually ignited when exposed to a fresh source of oxygen.


Vanthuyne explains that in spring when the sun warms the outside of the bin, warm air moves up near the outside wall of the bin and down through the centre of the bin. The cooler canola in the centre of the bin reabsorbs moisture and spoilage can occur.


“That's when you need to monitor the seed more regularly", Vanthuyne says. "This higher moisture zone favours the growth of storage moulds and eventually the seed may become damaged or start to heat.”


He advises growers to take out some canola from the centre of the bin or use aeration. "That way," he says. "you'll interrupt the increase in temperature and moisture in the central core and stabilize both moisture and temperature over the summer.”


Derwyn Hammond, Canola Council agronomist for Manitoba, agrees with this strategy but warns growers about some potential dangers in bins where heating is already taking place.


“We have already had some reports of heated pockets of canola flaring up or exploding in a few bins”, he says. When a hot spot develops in a bin, the spoilage leads to mould growth and increased respiration in the surrounding seed thus increasing moisture and temperature within the grain mass. If this cycle is allowed to continue, it will eventually lead to oxidation (burning without flame), which will increase the temperature rapidly and possibly lead to spontaneous combustion.


Hammond says that often these pockets of heated canola occur in the centre of large storage structures. The sealed bin and surrounding grain mass insulate them and limit the supply of fresh oxygen. However, if the heating produces temperatures near the flash point for canola oil (275 to 290 °C), then a supply of fresh air may be all that is required for the seed to ignite. This fresh air may be supplied through the removal of the surrounding seed within the bin or the use of aeration.


“If the seed does ignite, it will burn similar to oil or grease fires and should be treated accordingly,” Hammond warns. “Growers dealing with heated canola need to be careful to ensure their safety and that of their workers,” he adds.


Vanthuyne says if moisture and temperature are properly maintained, it's possible to store quality canola seed two to three years. “Although,” he adds, “canola with significant green seed content is less stable and requires extra care if it’s stored for long periods.”


He cautions growers to be extra vigilant this coming summer since a large portion of last year’s crop went into bins at moisture levels above safe long term recommendations. Regular maintenance of that seed while in storage is the key to avoiding heat damage.


Vanthuyne uses a chart to figure out what has to be done to keep stored canola in good shape for more than five months. He says if the temperature or moisture levels of the canola fall within the spoilage area of the chart, either the seed moisture or temperature or both need to be reduced. For storage longer than five months, canola should be binned below 8% moisture and below 15º C.


For more information in your area, contact:


John Mayko, Agronomic Research & Extension Manager, 780-764-2593
Derwyn Hammond, Manitoba, 204-729-9011
Jim Bessel, North Central & North Eastern Saskatchewan, 306-373-6771
David Vanthuyne, Eastern Saskatchewan, 306-782-7799
David Blais - Western Saskatchewan, 306-895-2122
Jackie Heck - Peace, 780-853-5261
Doug Moisey, Central Alberta, 780-645-3624
Matthew Stanford, Southern Alberta, 403-758-6660
This media release is part of the Canola Council’s Canola Advantage program.


The program 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, Food and Fisheries.