Just like the title says! Saw these today and a tree that I believe is an English Walnut but not sure. Any help is appreciated!
What are these and how do I get rid of them?
- Thread starter PA Dan
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JeffGu
Antagonist/Heckler
Those are Datan integerrima the Walnut Caterpillar Moth larvae.
They usually feed in big clusters, so you can pick them off and destroy them. They can do a lot of damage to the trees in years when their numbers are up. There is a bacterial insecticide that is used to control them around here, in the midwest, Bacillus thuringiensis that works pretty well. You must spray it on the trees while the caterpillars are still actively feeding, as it has no effect on the insects other life stages. It won't harm you or your dog/cat/alligator as it's a naturally occurring bacteria found in rotting wood. Sunlight kills it off after a few days, so you won't be starting a plague, or anything.
They usually feed in big clusters, so you can pick them off and destroy them. They can do a lot of damage to the trees in years when their numbers are up. There is a bacterial insecticide that is used to control them around here, in the midwest, Bacillus thuringiensis that works pretty well. You must spray it on the trees while the caterpillars are still actively feeding, as it has no effect on the insects other life stages. It won't harm you or your dog/cat/alligator as it's a naturally occurring bacteria found in rotting wood. Sunlight kills it off after a few days, so you won't be starting a plague, or anything.
If you only have a few clusters and they are low enough to reach you could just clip off those branches and drop them in soapy water. Otherwise, use the Bt (Dipel is one common name brand product with that active ingredient). Bt works best with the early instars. You have to look are more broad spectrum insecticides.
