WINNIPEG – Farmers and scientists in Manitoba are hoping a late start to the growing season will send an unwanted guest packing.
Two years ago, farmers started to mention to researchers that they noticed the occasional brown, mottled, cutworm-like caterpillar in canola fields. The insects are a little thinner than a pencil and up to four centimetres long.
But last fall, a farmer in Ste. Rose du Lac found thousands crawling in his truck after combining a canola field. There were also sightings near Swan River, Dauphin, Minn-edosa, Gladstone, Neepawa and Rosebank.
Read Also
Agri-business and farms front and centre for Alberta’s Open Farm Days
Open Farm Days continues to enjoy success in its 14th year running, as Alberta farms and agri-businesses were showcased to increase awareness on how food gets to the dinner plate.
“When you start seeing numbers like that, you know they’re eating something,” said Bruce Murray, a pest management specialist with Manitoba Agriculture.
But Murray said the Ste. Rose producer also reported great yields. He apparently got about 40 bushels per acre in the infested field.
Past the eating stage
Bob Lamb, entomologist at Agriculture Canada’s Winnipeg research centre, said farmers shouldn’t be too worried yet. With late seeding in many areas, by the time crops come up this year the caterpillars may have stopped feeding and turned into moths.
Lamb said cutworm problems often come and go quickly because of this timing factor.
But scientists want to identify the mystery guest and find out how it affects crops, so Murray collected about 100 caterpillars from the field this spring.
Lamb is feeding the caterpillars so they will develop into adult moths during the next month. So far they have eaten wheat, flax, mustard and canola.
Lamb said a graduate student and Rob Roughley, an entomologist from the University of Manitoba, have identified the caterpillar as belonging to the cutworm family. They will be able to narrow it down to the species once the worms become moths.
Then, the team can find out whether the worm has been a problem in crops before and how others have managed it.
Hundreds of species
Lamb said there are likely between 200 and 300 species of cutworm in Manitoba. The two most common are the infamous Bertha armyworm and the red-backed cutworm. These caterpillars hide in topsoil and like to mow down plants.
But their new cousin burrows into the stalks of plants and possibly feeds there.
Lamb said while he may not recognize every bug in a canola field, it’s unusual to come across an insect in large numbers that is not readily identifiable.
Murray said the insect hasn’t yet achieved pest status. He encourages farmers to contact extension agrologists in their areas should they spot the insect in their fields.
