Shade Tree catepillars
I believe I have Orangestriped Oakworms eating the leaves on my pin oak trees. I've been reading about Bt but wonder where I purchase it. Lowe's was no help. Didn't get over to Tractor Supply this evening. Can you tell me what products contain it? I had some Triazicide, and sprayed that on tonight. But can't find the full ingredient list.
Certified GKH Gardening Expert
Triazide is a pyrethroid insecticide with the active ingredient of gamma-Cyhalothrin and should be very effective for immediate knock down of the caterpillars on contact. If you mixed the solution according to label directions and got good coverage of upper and under side of leaves, the oakworms should be down and out with one application.
If you want to go organic next time, Bt is a biological control with no toxicity except for the target caterpillar pests. Timing is more critical than with the pyrethroid, early stage of development and feeding is best, the caterpillars have to ingest it to become affected. It usually takes a follow up spray to be completely effective. https://www.domyown.com/monterey-bt-insecticide-p-2821.html?sub_id=11262