Throughout the season, Flea beetles in canola and grasshoppers were two major insect concerns.
Flea beetles were abundant enough in the Northwest and Interlake regions to cause some farmers to have to reseed some acres of canola due to flea beetle damage. The heavy flea beetle population started being noticed in late July and by August, there were reports of heavy activity on podded canola.
Grasshoppers were a bigger concern in mid-June to late-August. Insecticide applications for the bug were reported in the Northwest, Interlake, and Southwest regions. There was also grasshopper control reported on hemp in the Northwest region in June.
From mid-July to mid-August, Diamondback moth was a concern for canola growers in some regions. The highest trap counts in the northwest region came from The Pas and Bowsman while Selkirk and Clandeboye saw the highest trap counts in the Interlake region. Some fields in the Interlake, Eastern, and Central regions were affected by alfalfa weevil in June.
As well, aphids did not seem to be much of an issue in the Interlake and Northwest regions however they were abundant in late june to late july in small grains in other regions, but some of those fields had an abundance of their natural enemies.
The summary also noted that for the first time, Western corn rootworm and cannabis aphid were found in Manitoba. The cannabis aphid were found and identified at a greenhouse in Eastern Manitoba.
The full Manitoba Agriculture insect summary for 2021 can be found here.
