During these periods, they may defoliate a number of garden plants. The insect will attack most garden crops, especially tomatoes. Cabbage Worm Description. The larva of the cabbage looper is a slender green caterpillar with a thin white line located on each side. Its body tapers slightly toward the head.
Adults are dull-colored moths.
The female lays eggs in the night. The imported cabbage worm is leaf-green with a velvety appearance. Adults are white butterflies with three or four black spots located on the wings. They may be seen flitting around gardens during daylight hours. These two insects are often found on the same plant, and they damage the plant in the same manner.