This elusive, 2 inch long, brilliantly colored caterpillar, which protrudes a pair of orange horns when disturbed, is rarely seen in gardens. Although technically a pest, it’s so pretty you may want to overlook the paltry damage it does. Left alone, it will metamorphose into a gorgeous black and yellow swallow tail butterfly another reason to admire it, not kill it.
Target: Carrots, celery, dill, parsley, parsnips, queen Anne’s lace.
Damage: Leaves and stems are nibbled.
Life cycle: Female swallowtails lay tiny, round green eggs on the leaf tips of host plants; small brown larvae hatch out, feed, and develop into large tricolored caterpillars. The insect overwinters as a pupa in cold climates, as an adult in warm climates. There are two to four generations a year.
Notes: Rather than killing the caterpillars, try moving them to a more expendable host plant.