Cabbage White Butterfly

(Pieris rapae)

Identification Cabbage White on Wild Mustard

The Cabbage White buttefly has white or pale yellowish-white wings with black tip on its forewing. The upperside of the female forewing has two black spots while the male has one. Both sexes have one black spot well out along front margin on the upperside of the hindwing. The underside of the forewing is white with yellowish apex and two black discal spots in both sexes; while the underside of the hindwing is uniformly pale yellow in both sexes.  The typical wingspan of the Cabbage White is 1.2 to 2 inches (30 to 50 mm).

The Cabbage White caterpillar is green or bluish-green with thin yellow dorsal line (sometimes faint or absent) and a lateral line composed of pairs of yellow spots, with a black central dot and a body covered with short fine hair. 

Habitat

The White Cabbage Butterfly prefers open spaces but may also be found in treed areas, backyard gardens and agricultural fields.

Season

The adults fly from early Spring to September.

Food

The caterpillar eats cabbage, many other crucifers and related plants. The butterfly feeds on nectar from a very wide array of plants, including wild mustard, dandelion, red clover, aster, and mint.

Life Cycle

The females lay single eggs on undersides of host plant leaves. It overwinters as a pupa inside a chrysalis attached to some substrate with two or three generations per year.

Remarks

This species is a resident but has become a significant pest. It was probably introduced between the late 1800s and early 1900s. Biological controls have been attempted using a pupal parasite. In other countries bacterial and viral diseases have provided some biological control; while the parasitic wasp Cotesia glomerata, has also be used. 

As a major pest this butterfly should not be encouraged.