2011 Plant Prescription for Diagnosis: Eastern Tent Caterpillar
Larvae are present from April through mid-June. Treatment is most effective when caterpillars are small. Destroy the web in the evening during April with a stick.* If further control is needed, use Insecticides in April and May, penetrating the silken nests for good control. Spray all around the web. Use one of the following insecticides:
Insecticidal soap (Concern Insect Killing Soap)
Horticultural Oil (All Seasons or Volck Oil)
Neem oil (Bonide Rose Rx) Green Light Neem II
Bt (Bacillus thurigiensis – Thuricide) – Spray only in evenings, when less than 1/2” long
Bayer 3-in-1 Insect, Disease, & Mite Control
Permethrin (Borer-Miner Killer Concentrate)
Bifenthrin (Ortho MAX Lawn and Garden Insect Killer conc.)
Maxide Insect Killer
Mix according to label directions and apply only the recommended dosage. Apply material only to plants specified on the label.
*If you see white “seeds” on the caterpillar head, those are parasitic tachinid fly eggs. Spraying with Bt won’t harm the flies, which will continue feeding on that dead caterpillar body.