Cabbage worm
The term cabbage worm is primarily used for any of four kinds of lepidopteran whose larvae feed on cabbages and other cole crops. Host plants include broccoli, cauliflower, Brussels sprouts, collards, kale, mustard greens, turnip greens, radishes, turnips, rutabagas and kohlrabi. This small group of similar pest species is known to agriculturists as the cabbage worm compte butterflies (family Pieridae, type genus Pieris, garden whites).
The Small White (P. rapae) is a small, common, cosmopolitan butterfly whose caterpillar has fine, short fuzz and is bright green; it prefers cabbage, broccoli and cauliflower. A larger Old World form (P. brassicae) is called Large White. A common North American form (P. protodice) is known as the southern cabbage butterfly. The Green-veined White (P. napi) occurs in Europe and North America.
The cabbage looper (Trichoplusia ni) is a member of the moth family Noctuidae. The caterpillar is smooth and green with white stripes. It is called a "looper" because it arches its body as it crawls, inchworm-style. This species is very destructive to plants due to its voracious consumption of leaves. It is not restricted to cole crops; other plant hosts include tomato, cucumber, and potato. The adult of the species is a nocturnal brown moth.