Black Swallowtail Caterpillars Munching on Herbs

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If you like to garden you probably like butterflies. You probably also grow some herbs like fennel, dill, or parsley. Your love of butterflies and herbs may collide when you see a pot of dill stripped down to a bare stalk. The culprit is likely eastern black swallowtail caterpillars.

Image of Black swallowtail caterpillar

Black swallowtail caterpillar on fennel. Photo: GG Frank

The ones I have seen lately are large full grown caterpillars which are beautifully striped in black, yellow, and white. However, the younger larvae are black and orange and not nearly as pretty. Try to tolerate feeding by these caterpillars or move them to another suitable host. They feed on plants in the carrot family, Apiaceae. So if you don’t want them on your herbs move them to some Queen Anne’s lace, wild parsnip, or other related plant.