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Grain beetles on the rise after wet harvest

Requests for pesticide certificates are up, likely because more grain is being turned away at elevators

More farmers are requesting permits to use pesticides to kill grain beetles in their bins. But the fumigant Phostoxin doesn’t work when temperatures are below 12 C.
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Farmers are finding more grain beetles and that has provincial ag officials fielding more requests for renewals or issuing new certificates under the Farmer Pesticide Certificate Program.

“We see it almost every year in southern Alberta, but it’s creeping up to central Alberta, too,” said provincial crop specialist Harry Brook.

“After the very difficult harvest, there is plenty of wet and damp grain. Variable temperatures are causing grain heating and that attracts grain beetles. That is telling me that people are taking their grain to the elevator and having it turned back because there are live insects in the bin and the truckload of grain.”

There are several ways to deal with insects such as grain beetles. The Farmer Pesticide Certificate provides information on effective and safe use of pesticides. An endorsement is needed to access the grain fumigant Phostoxin.

“But it can be dangerous which means there are a lot of safety issues around using it,” said Brook. “Once it is in the bin, you have to seal it off. It needs temperatures in the grain bin of 12 C to 15 C or better before it will activate.”

If it is colder than that, producers cannot use the fumigant.

“It is not effective, and it can be dangerous because those pellets then don’t break down,” he said. “It could be an issue later when you’re taking the grain to the elevator.”

Cold weather can provide one of the easiest ways to deal with grain beetles in a bin, but inside temperatures need to be -20 C or lower for up to two weeks, said Brook.

“When it gets down to -20 C, aerate your grain and keep it at that temperature. Keep it at that temperature for two weeks, and you will effectively kill off all insects in that bin.

“Aeration is effective under cold conditions, as it freeze-dries the beetles. If the temperatures are only -15 C, keep it down for three or four weeks, and that will kill them as well. The warmer it gets above -20 C, the longer it takes to kill them, but it does. It is one of the few effective and simple means to control the beetles.”

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