Other Insect Pests Appearing

Cabbage seedpod weevil has been seen in canola fields throughout southern Alberta and southwestern Saskatchewan as crops have started to bolt, with some fields in early flower. Reports are that populations are lower than last year with many fields below threshold at this time. The economic threshold for the weevil is 20 to 30 weevils in 10 sweeps, depending on crop price. For more information on the cabbage seedpod weevil, refer to the cabbage seedpod weevil section at the following link: http://www.canola-council.org/contents10b.aspx

All three provinces report increasing grasshopper populations although it appears as if few, if any, canola fields have been sprayed to date. Spraying in cereals has occurred in areas of the Peace region in Alberta and high populations warranting spraying were found in a canola field near St. Michael, AB. 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: http://www1.agric.gov.ab.ca/$department/deptdocs.nsf/all/agdex6463

Very few diamondback moth adults have been caught in monitoring traps throughout western Canada this year. However, there are reports of larvae in canola fields in Saskatchewan near Raymore, Swift Current and Val Marie. Populations observed so far 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: http://www.agriculture.gov.sk.ca/Default.aspx?DN=688b2f99-ad99-423d-900c-c01a1c45d8a