Wireworm puts small holes in potatoes.

Wireworm puts small holes in potatoes. (CBC)

A pest that caused $6 million in damage to P.E.I. potato crops last year is spreading.

The wireworm is a type of click beetle. It used to be found only in isolated areas, but now it’s showing up across the Island, the P.E.I. Potato Board said. 

The worm makes holes in potatoes and other crops, making them unfit for sale fresh or processed.

The potato board surveyed growers about wireworm to find out more about its impact.

“It's a serious pest. It's increasing in its importance here. And not just potatoes, it's also affecting our horticultural crops, like carrots. And we're seeing some damage in other crops like cereals and forages as well,” said Greg Donald of the board.

It cost the potato industry $6 million last year in lost crops and the expense of chemicals used to fight the pest.

“That figure is certainly larger than we thought and I would say it’s continuing to increase,” he said.

Hope for chemical solution

Research on using brown mustard and other crops in rotation with potatoes has been somewhat effective in controlling wireworm.

But Thimet, the chemical most widely used, will be taken off the market next year. He said a product using a different chemical, Bifenthrin, is being looked at by Canada’s Pest Management Regulatory Agency.

“We're hopeful that product will be registered this spring, so we can at least have one year to compare its effectiveness to Thimet,” he said.

A day-long workshop on wireworm is being held next Tuesday to update growers on the latest research on the pest and tell them what they can do to try to curb its devastating effects.