Answer: Your description of the pest could fit one of many insects, so it's difficult to say for certain how to control the problem. The botanical Bt (Dipel) is registered for use against most caterpillars, so try dusting it on your plants. It's a stomach poison so the caterpillars will continue to feed until they've consumed enough to kill them. If you're only finding a few pests, why not pick them off the plants and destroy them?
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