Extension > Garden > Diagnose a problem > What insect is this? > Garden Pests > Caterpillars, maggots, grubs, and similar immature insects - Larger than 3/4 inch long > Black swallowtail
Black swallowtail
Papilio polyxenes

Jeff Hahn, University of Minnesota Extension
Description: Up to 1 1/2 inches long.
Where/When: Feeds on many plants in the Umbelliferae including parsley, carrots, dill, fennel, celery, and Queen Anne's lace. Prefers to feed on the flowers and seeds of these plants. Present July to September.
Significance: Feeding is rarely sufficient to seriously injure plants.
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