Cabbage Looper - Trichoplusia ni . Also known as cabbage worm. Loopers reach approximately 1 inches long and have three pairs of slender legs near the head and three pairs of larger prolegs at the rear end. The middle section is legless and is looped when the insect is moving. Larvae are the damaging stage of this insect.
Worms feed on the undersides of leaves between the veins and leave ragged holes.
They also feed on cabbage, cauliflower and broccoli heads. Larvae may be present from early spring to late fall. Other sprays can also be used but weekly treatments will be needed to control newly hatched larvae. It is important to thoroughly cover the underside of the leaves as this is where the looper feeds.