Answer: Those caterpillars can be the larval form or a number of different insects. I'd suggest trying to spray a botanical spray such as pyrethrum on the roses to stop their feeding. If the caterpillars are in the Lepidoptera family (hard to say without seeing them), then you can spray Bt on the roses. Bt is a bacterial product that attacks only the caterpillars in that family. It's safe for humans, animals and other insects.
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