Celery Worm - Carrot Worm
Celery Worm (Papilio polyxenes) Also called the carrot caterpillar and parsleyworm, adults are green with yellow and white spotted black bands and can grow up to 2 inches long. Two orange "horns" just behind the head are projected when the caterpillar is disturbed.
This caterpillar is the larva of the black swallowtail butterfly. The adult butterfly is black with two rows of yellow spots on the outer border of the wings and light blue areas on the lower wings; it has a wingspan of almost 4 inches.
The most common host plants of the carrot or celery worm include carrots, celery, parsley, dill, and parsnip. This pest chews leaves and stems and destroys tops but is seldom numerous enough to reduce yield. They are found throughout United States. Hand-picking the caterpillar is usually sufficient to control, but try these organic means if the problem is out of hand.
Photo courtesy of Rowena Hopkins, Moncton Naturalists' Club
For control products and more information please see our Caterpillars and Moths Control page.