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Pea weevils munching northward in Alberta thanks to mild winter

The pea weevil, an insect with a big appetite for pea crops, is spreading farther north in Alberta than ever before.

Insects can reduce crop yields up to 17%, leaving signature mark in their wake

Doug Sell surveys the damage of pea weevils on his pea farm near Carbon, Alta. (Andrew Brown/CBC)

An insect that has an appetite for pea crops is spreading in Alberta.

Pea weevils are moving north, thanks to warmer temperatures and more availability of their favourite food.

Pea weevils like to eat fava bean and field pea crops. (BioWeb)

Researchers say although the pests been around for years, more farmers are seeing them farther north than ever before.

Farmers like Doug Sell are seeing the damage from pea weevils for themselves.

"This plant has been quite badly compromised," says Sell, surveying his crops.

"You'll see a very distinct half-moon chew-mark in the leaf."

Between 20 and 30 per cent of his 65 hectares of peas are affected, Sell says.

Pea weevils leave signature half-moon chew marks on the leaves of pea and fava bean crops. (Andrew Brown/CBC)

Weevils chew on fava bean and field pea crops, according to research scientist Hector Carcamo.

Fava beans, also known as broad beans, are considered a pulse crop. They are tall plants with hollow stems and strong tap roots.

Until this year, the weevils have mostly been spotted south of Highway 1. But they're moving north, Carcamo says.

"We had a very mild winter this past year and when we have mild winters then the proportion of insects that survive is a little bit higher."

More farmers are growing fava bean and field pea crops as well, Carcamo says.

The insects can reduce yields by up to 17 per cent. Carcamo advises farmers to consider using an insecticide if 30 per cent of their crop is showing signs of damage.

With files from the CBC's Andrew Brown

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