Hungry caterpillars on my delphinium! - Ask Extension
I found some damaged and curled leaves on my delphiniums last night. I uncurled the leaves and found these larvae and their waste.
OK to use Bt spr...
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Hungry caterpillars on my delphinium! #872542
Asked June 11, 2024, 3:01 AM EDT
I found some damaged and curled leaves on my delphiniums last night. I uncurled the leaves and found these larvae and their waste.
OK to use Bt spray to get rid of them?
Anchorage County Alaska
Expert Response
Hi Barbara,
These do appear to be caterpillars but to confirm it would be helpful to see a side view where I can see the legs clearly. This will help me confirm these are not a sawfly as Bt is not effective on sawflies. Caterpillars have at most 5 fleshy "prolegs" after their regular jointed legs, where as sawfly larvae have more than 5.
If you can confirm this is a caterpillar then Bt var. kurstaki is a management approach you can take. If the infestation is small you also can remove the larvae by hand or by shaking them off the plant.
These do appear to be caterpillars but to confirm it would be helpful to see a side view where I can see the legs clearly. This will help me confirm these are not a sawfly as Bt is not effective on sawflies. Caterpillars have at most 5 fleshy "prolegs" after their regular jointed legs, where as sawfly larvae have more than 5.
If you can confirm this is a caterpillar then Bt var. kurstaki is a management approach you can take. If the infestation is small you also can remove the larvae by hand or by shaking them off the plant.
