Cabbage Butterfly, common name applied to the adult of the imported cabbageworm, a member of the whites and sulphers family of butterflies. The name is also loosely applied to several other related species whose caterpillars feed on plants in the mustard family. The cabbage and other related plants secrete a chemical to which the butterfly is attracted. The butterfly deposits eggs on the leaves, on which the larvae feed and grow to maturity. The infested foliage is toxic upon consumption by animals. About a dozen species that follow these habits are found in North America, the most destructive of which is the imported cabbage butterfly, a European species introduced into Canada about the middle of the 19th century and now common throughout the United States. The fully grown larva, or caterpillar, is about 4 cm (about 1.5 in) long and green with a lemon-yellow dorsal band. It not only eats the leaves of the plants before heading time but also burrows through the heads. The butterfly has a wingspan of about 3 cm (about 1.2 in). The tops of its wings are white; the forewings are tipped with black. The forewings of the female have two central black dots, and those of the male, one. The undersides of the wings are pale yellow. Related species include the large white, a European variety; and the southern cabbageworm butterfly, or checkered white, a common American variety.
Scientific classification: Cabbage butterflies belong to the family Pieridae. The imported cabbage butterfly introduced into Canada is classified as Pieris rapae. The large white is classified as Pieris brassicae, and the southern cabbageworm butterfly as Pieris protodice.