Both flea beetles and cutworms attack canola when it’s young. Both pests can cause significant yield loss.
Flea beetles are the most common insect pest in canola and they cause the most yield damage under adverse conditions when canola is already struggling to emerge.
The crucifer and striped flea beetle species both have the ability to cause significant damage early in the season. A canola plant can have trouble bouncing back from flea beetle feeding in the seedling and early vegetative stage.
Any weather situation where seed is slow to emerge from the ground puts canola at risk of flea beetle damage. Seed treatments will protect canola seed for a time, but your canola is vulnerable if it is slow to emerge and doesn’t reach the three- to four-leaf stage before flea beetles start feeding.
Crucifer flea beetles were the main species of flea beetle in the past but they have been joined by striped flea beetles to add to the problem across Western Canada.
The incidence of striped flea beetles across the Prairies is rising
Crucifer beetles used to represent most of the flea beetle population. Striped flea beetles have moved south and east across the Prairies infesting places like Southern Manitoba where they were once a rare occurrence.
Striped flea beetles emerge first, one to four weeks earlier than crucifer flea beetles. Peak emergence of crucifer flea beetles occurs when ground temperatures reach 15°C.
Flea beetles tend to emerge around the same time as early seeded canola, when it is small and susceptible to insect damage. If the flea beetles emerge first, they will feed on brassica weeds (stinkweed, flixweed, wild mustard, volunteer canola) until the canola crop comes up.
Pounce® 384EC insecticide controls both striped flea beetles and crucifer flea beetles in canola. It is an effective foliar solution to support canola seed treatment packages.
Cutworms move from plant to plant
Cutworms are equally opportunistic, clipping or severing stems of seedlings before they are strong enough to withstand the damage.
Cutworm damage is commonly seen in the field from the end of May to the end of June. There are over 20 species of cutworms. They overwinter in the soil as eggs or larvae, depending on the species. They prefer dry conditions and emerge and start feeding again when the temperatures climb.
Since cutworms prefer dry conditions, pay special attention when scouting on hilltops or on south-facing slopes where the ground dries more quickly. Zero-in on bare patches. Cutworms will feed on one plant and then move to the next one. The Canola Council of Canada says that economic threshold is met when 25-30% of a stand is reduced.
Coragen® MaX insecticide can be applied any time, day or night. It controls hatching insects all the way through to adult stages and as a bonus, delivers superior residual activity.
Cutworms are nocturnal but that doesn’t mean you have to be. Since Coragen® MaX insecticide has superior residual and it controls upon ingestion, you have the freedom to spray during the day. When cutworms come out to feed at night, Coragen® MaX insecticide is there waiting for them.