OSR cabbage seed weevil

[Wilbada]

Seeing a lot in my OSR. Are other people seeing much and are you putting an insecticide in with mid flowering spray?

 

[DrWazzock]

When we actually had a crop that got to flowering we were loathe to spray it with insecticide as bees were foraging. We were also told that any insecticide would only have a one off knockdown effect and so it would be unlikely we’d actually hit many egg leg laying flies as egg laying occurs over a time period. I believe it’s the pod midge that makes the hole and some sort of fly that lays the weevil egg in it.
So we didn’t spray and I don’t recall a massive yield hit. Sclerotinia usually did that job. But all this is quite anecdotal not verified agronomic advice which really you should seek. What do NIAB TAG or such like say?

 

[Brisel]

When we actually had a crop that got to flowering we were loathe to spray it with insecticide as bees were foraging. We were also told that any insecticide would only have a one off knockdown effect and so it would be unlikely we’d actually hit many egg leg laying flies as egg laying occurs over a time period. I believe it’s the pod midge that makes the hole and some sort of fly that lays the weevil egg in it.
So we didn’t spray and I don’t recall a massive yield hit. Sclerotinia usually did that job. But all this is quite anecdotal not verified agronomic advice which really you should seek. What do NIAB TAG or such like say?

The seed weevil makes the hole. Bladder pod midge lays its eggs inside which will later feed on the seed & split the pod close to harvest.

Threshold is one weevil per plant away from the headland. As you go through with the sclerotinia spray, if your radiator grill is full of weevils them you might consider treating, though of course that means travelling through again which many folk rightly don't want to do.

Remember than an insecticide will also kill your pollinators. Never mix triazoles with pyrethroids as the repellent part of the pyrethroid is masked by the triazole. Just don't do it!

Control of cabbage seed weevil on oilseed rape | AHDB

Find out how to identify and control weevils to prevent direct and indirect yield losses.

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