While excess moisture frequently causes spoilage in stored grain, damage from insects can also account for significant losses. But with preplanning and monitoring, insect damage can easily be reduced, or even eliminated. According to the Canadian Grain Commission, clean bins and cool grain are the key.
Thoroughly cleaning storage bins between seasons is the first step to eliminating the risk of insect damage. That means cleaning out the dust, debris and dockage left behind after emptying a bin, which removes insects’ food sources. A good broom and some elbow grease, a pressure washer or a vacuum will all do a good job tidying up inside bins. And don’t forget to clean aeration systems, too.
Once the bins are refilled, keeping stored grains below +15C and under 14.5 per cent moisture content is the next step. Cool temperatures prevent any existing insects from reproducing. And keeping things dry prevents fungi from growing, which can be a magnet for insects.
“If there’s sufficient moisture for fungi to grow, warmer temperatures make it worse,” says Randy Clear, a mycologist with the Canadian Grain Commission. “Fungi is always there.” The heat produced inside a bin filled with damp grain creates an ideal environment for growth.
If you are already dealing with an insect problem, there are several chemical insecticides on the market that can be used to treat an empty bin before the new crop is loaded in. But you need to know what type of grain will be stored in the bin next before using any chemical.
“When you’re treating a bin (to store oilseeds) don’t use malathion,” says Harry Brook of the Alberta Ag-Info Centre. Flax and canola seeds can absorb the residue from it, contaminating the entire bin. “All we need is one sample being tested for export and found positive (for malathion) and we’d lose that market,” he adds.