Q&A – What is this mass of caterpillars on my walnut tree?

Question:
What is this mass of caterpillars on my walnut tree?

Answer:
These are walnut caterpillars. They will migrate into the canopy of the tree to feed on the leaves. They can be controlled at this stage by scraping them off the bark into a container of soapy water or by using an insecticidal soap.

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Related Resources:
Walnut Caterpillars
Walnut caterpillar