Number of Insect Pests Found

There were a couple of reports of cutworms in Saskatchewan but it appears as if larval feeding is winding down as they are beginning to pupate. More information on cutworms is available at:

Cabbage seedpod weevil threat is also winding down in southern Alberta and southwestern Saskatchewan as many crops are well into or have finished flowering. Only fields that are just coming into flower are still at risk. Reports are that populations were lower than last year and in many fields were below threshold. The economic threshold for the weevil is 20 to 30 weevils in 10 sweeps, depending on crop price. More information is available in the cabbage seedpod weevil section at the following link:

All three provinces report increasing grasshopper populations although it appears as if few, if any, canola fields have been sprayed to date. Grasshoppers may become a concern in canola adjacent to a field cut for hay as the insects migrate to continue feeding. Continue scouting for grasshoppers because if caught early perimeter spraying may be all that is needed.  A specific economic threshold for grasshoppers in canola has not been established as it is not a preferred host crop, but it is currently considered to be in the range of 7 to 14 per m2, depending on the crop value and cost for control. More information on grasshoppers is available at the following link:$department/deptdocs.nsf/all/agdex6463

Few diamondback moth adults have been caught in monitoring traps throughout western Canada this year.  Populations of larvae observed in parts of Saskatchewan are below the economic threshold of 100 to 150 larvae per m2 in immature and flowering fields or 200 to 300 larvae per m2 in flowering and podded fields. More information on diamondback moth is available at the following link:

Red turnip beetle was sprayed on a limited number of acres via perimeter spraying in the Peace region of Alberta. This insect moves into a field by migrating from a neighboring field that was in canola last year. As a result, control can usually be achieved with spraying field edges. More information on this insect is available at:

Lygus bugs were reported near Raymore, SK, Morinville, Grimshaw, and La Crete, AB. The population at La Crete was sprayed. Other populations are below threshold and being monitored. The economic threshold of lygus bug in canola ranges depending on crop price and cost of control. Fields should be monitored during flowering but there is no scientific evidence that yield loss occurs at this stage. Control is economical when the crop is podded and populations exceed the economic threshold. There may be an opportunity for some migration of lygus bugs into canola from alfalfa crops now being cut for hay. More information on lygus bugs is available at the following link:

Cabbage root maggots were reported in Saskatchewan and Alberta.  A couple of fields in central Alberta had considerable damage. Unfortunately there are only cultural management tools for this insect pest. More information on cabbage maggot is available at:

Bertha armyworm adult moths have been caught in traps across western Canada recently. Moth numbers at all locations are low resulting in a low risk assessment at this time. Trap results will continue to be reported in Watch in the coming weeks. More information on bertha armyworm is available at: