Suspected cutworm actually a cranefly larva

Here’s another example why proper pest identification is important. The “suspected” redbacked cutworms found in the Carrot River area last week turned out to be cranefly larvae, commonly called “leatherjackets.” They were the same size as cutworms but were at a more advanced stage than redbacked cutworms would be at this time of year. They didn’t curl into a ball the way cutworms do. See the photos below. The second photo shows the cranefly larvae beside a wireworm.

Cranefly and cranefly larvae are not known to cause economic damage in canola, so insecticide control is not warranted. Craneflies overwinter as larvae in the soil quite close to the soil surface. They feed on decaying vegetation and crowns, underground stems, or roots of a variety of plants. Grasses are preferred, but they actually have a broad host range. Juliana Soroka, entomologist with AAFC in Saskatoon, has seen them damaging potatoes around Outlook, Sask.

Had they been cutworms, the grower may have prepared to spray. When dealing with any pest, identify it correctly before making a control decision.Growers in this region will be on the lookout for cutworm this year after a bad outbreak in some fields last year.  Alberta Agriculture and Rural Development is collecting cutworms to grow to adulthood and identify. Growers and agronomists who find cutworms and would like to identify them, contact Scott Meers entomologist with AARD.