U.S. storms blow record number of moth into Ontario

Black cutworm moth levels are incredibly high in the region, after the insects were forced north by early storms in the U.S. Midwest.
Black cutworm moth levels are incredibly high in the region after being forced north by the early storms in the U.S. Midwest. (University of Florida)

An unseasonably early tornado season in the U.S. Midwest has blown a potentially big problem to southern Ontario farms.

The number of black cutworm moths is incredibly high in the region. The insects were forced north by the storms.

The moths lay eggs in low-lying weedy patches in and around fields. The eggs hatch, and the larvae eat sprouting field corn crops.

"There's no reason to be worried, but there is every reason to be diligent, right now," said Dale Cowan, an agricultural specialist with AGRIS, a southwestern Ontario agricultural co-op.

According to the Ontario Ministry of Agriculture, Food and Rural Affairs, the young caterpillars cut off young plants near ground level, causing them to wilt and fall over. A single larva may destroy several seedlings. The larvae feed at night.

"What you see the next day is plants toppled over or leaf pieces sitting on the ground," Cowan said.

By then, it's too late to do anything.

The moths can be controlled, but if a farmer isn't paying attention, he or she could lose half their crops.

"It’s quite an economic impact if farmers aren’t looking," Cowan said.

Cowan said farmers were hoping the frost in late April would kill the moths and the larvae, but it didn't.

"We know they are there. We just have to wait for them to develop," Cowan said. "Things are in check right now, but things could change quite quickly."