Beneficial Insect Spotlight: Checkered White butterfly
The Checkered White butterfly is also known by its Latin name, Pontia protodice, and is quite abundant across the United States. It is often confused with its close relative, the Western White (1) butterfly, which is found west of the Rockies (2). Checkered Whites are often found in dry, open fields, along roads, on farmland, and even in residential areas where they seem less affected by city sprawl than other species.
The Checkered Whites love all members of the mustard family (including peppergrass and watercress), and choose these as their host plants, in addition to broccoli, collard and cabbage. Adult butterflies lay their eggs one at a time on the leaves of these plants, where the growing caterpillars live out their lives, happily munching away on the buds, flowers and leaves. The eggs are barrel-shaped and are yellow when laid, but then turn orange (3). Caterpillars are soft green to gray-green in coloration with faint yellow stripes. They can be found on their host plants and are more commonly known as cabbageworms. As such, they are sometimes considered to be a minor pest on cultivated crops such as broccoli. Adult butterflies like to sample a wide range of nectars, but seem to prefer Purple Coneflower (Echinacea) and purpletop Verbena.
You can identify Checkered Whites by their distinct markings. They are often almost completely white butterflies. Males are less colorful with fewer patterns, but have at least two black spots on their forewings. Females display the more identifiable checkered pattern in black, gray and white on the edges of their forewings. Identification is a little more difficult west of the Rockies where Checkered Whites can be found along with the Western Whites. Experts say that Western Whites have a slightly darker checkered pattern than their cousin, but the easiest way to tell them apart is by comparing males of the two species. The row of dark spots on the male Western White is darker than the spots of the male Checkered White, and the hind wing is devoid of coloration or pattern. Checkered Whites can produce three generations between March and November in cooler climates and four to five generations in warmer climates like ours.
The Checkered White butterfly is a beneficial insect because it is a widespread pollinator and an important food source for many vertebrates. When you consider that one-third of the world’s cultivated crops depend upon the work of pollinators like butterfly and bees, and that many species of butterfly and bees have been harmed by destruction of habitats and city sprawl, it becomes clear how important this species is! In addition, butterflies are beneficial to humans for their aesthetic qualities. Many species are brightly colored and so capture the attention and marvel of many people. Just watching the whimsical flight of butterflies is enough to lift the spirits! The Checkered White, for example, has a fast and erratic flight pattern and likes to stay near the ground and in the open (4).
We had a visit from a female Checkered White butterfly this afternoon. She checked out several flowers, including the whirling butterfly Guaras, purple moss Verbena and what seemed to be her favorite, the Copper Canyon Daisies. Meanwhile, the large Black Swallowtail caterpillar has left the parsley, I assume to find a nice place to make its chrysalis before emerging as a butterfly in a couple of weeks. The little guy, however, is still munching away on the parsley!