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Beet Armyworm top
Beet armyworm, Spodoptera exigua (Hubner), hatch from egg masses and feed in groups on the undersides of leaves.
Suggested Management: The beet armyworm has few effective parasites, diseases, or predators to lower its population. However, effective chemicals for beet armyworm control are available to commercial vegetable producers.
Cabbage Aphid top
 
Cabbage aphids, Brevicoryne brassicae, are troublesome. Aphids cluster on the underside of leaves and suck sap, causing the foliage to curl, wilt, or become distorted. Plants may be killed or rendered unmarketable. Aphids are pale green and have cornices, or points, on the abdomen. Cabbage aphids have a gray waxy coat and can be winged or wingless.
Suggested Management: Cultural practices and the use of resistant varieties help prevent cabbage aphid infestations. Row covers physically protect seedbeds from these insects. Good weed control and the destruction of crop residue reduce overwintereing populations. Planting resistant varieties may also help. Apply chemical treatments as needed.
Cabbage Looper top
  
  
The eggs of the cabbage looper, Trichoplusia ni (Hubner),are round and laid singly. Early instar larva of the cabbage looper have black heads and spots on the body, and late instar larva are light-green, smooth, and loop when they move. The adult, however, is a brownish-gray moth with a figure-eight design in the forewing. It is a night flyer that migrates into North Carolina in June in most years. Moths are attracted to black-light insect traps, and males are attracted to sex pheromone traps (Hartstack screen traps).
Suggested Managament: Trichogramma wasps exist naturally and can be introduced to attack eggs. Scouting for larvae before and after sprays with records will show the level of control obtained, and may indicate whether and when additional sprays are needed. Some varieties of cabbage are tolerant. Natural enemies help to control these pests, but in most cases, chemical control of larvae is necessary.
Cabbage Maggot top
 
The cabbage maggot, Htlema brassicae (W.), is the major soil pest of the cole crops grown in the higher elevations of North Carolina. The white, legless maggot has a pointed head and grows to be 1/4 inch long. The fly resembles a small, common house fly. It is 1/4 inch long, is gray with three distinct black stripes along the abdomen.
Suggested Management: Cultural practices such as planting in late May or early June, careful selection of seedbed location, and elimination of weed hosts can help prevent severe infestations. If planting is delayed until the last week of May or the first week of June, few flies will be present to deposit eggs. Seedbeds located as far as possible from growing areas, and protected from egg-laying flies with a row cover, are less likely to be infested. Obtaining transplants grown at elevations below 3,000 feet will eliminate the danger of introducing the maggots on infested transplants. Destroying turnip and cabbage stumps and weeds such as wild mustard in the fall will eliminate many larvae or pupae. Proper fertilization and good soil practices also lessen maggot damage by improving plant tolerance. Cabbage maggots often require chemical control. An insecticide can be broadcast and incorporated just before planting seed or setting transplants. A drench applied after transplanting may also be effective.
Cabbage Worm top
The eggs of the imported cabbage worm, Pieris rapae (L), are elongated and laid on end singly. Early instar larvae have brown heads and are light green and hairy. Late instar larvae are velvety green, hairy, and slow moving.
Suggested Management: Trichogramma wasps exist naturally and can be introduced to attack eggs. Scouting for larvae before and after sprays with records will show the level of control obtained, and may indicate whether and when additional sprays are needed.
Corn Earworm top
The corn earworm, Heliocoverpa zea (Boddie), also referred to as the cabbage headworm, is a late season pest.
Suggested Management: Check cabbage closely for earworms between June and September. Avoid planting cabbage near field corn. Cultivating fields after harvest kills numerous pupae in the soil and exposes many to birds and other predators. Direct selective sprays to cabbage heads as soon as earworms or damage are observed.
Cross-striped Cabbageworm top
The cross-striped cabbageworm, Evergestis rimosalis, is a late season pest. Larvae are bluish-gray with tiny black transverse stripes.
Suggested Management: Examine fall-planted cole crop plants for cabbage webworms as soon as the plants emerge or are set out. Spray as needed. Early detection on the fall crop and sprays are required to control the cross-striped cabbageworm.
Diamondback Moth top
 
Eggs of the diamondback moth, Plutella xylostella (L), are small and laid in small groups. Early instar larvae have black heads. Late instar larvae are very light green, pointed at both ends, and wiggle fast when disturbed. They also spin a silken thread. Adults are small 1/4 inch long grayish-brown microlepidoptereans. When at rest, their wings come together to forma line of white diamonds down the back. Moths are active during the day and males are attracted to sex pheromone traps (water pan traps).
Suggested Management: Trichogramma wasps exist naturally and can be introduced to attack eggs. Scouting for larvae before and after sprays with records will show the level of control obtained, and may indicate whether and when additional sprays are needed. Diamondback moth caterpillars can be controlled with the same insecticides used on other caterpillars. If pests are resistant to certain insecticides, tank mixes of frequent sprays may be necessary. Although a number of parasites, diseases, and other predators prey on larvae and pupae, these natural enemies are often destroyed by insecticides.
Harlequinn Bug top
  
The harlequinn bug, Margantia histrionica (H.), is a hemiptera, or a true bug. It is a major pest of collards, turnips, and many cole crops. This black, shield-shaped bug is brightly colored with orange, red and yellow markings. The oval nymph looks like the adult, but is slightly smaller and lacks wings.
Suggested Management: Populations of overwintering adults can be reduced by plowing under field debris as cold weather arrives. Destruction of weeds within fields and among fence rows also limits overwintering sites. In addition to cultural practices, resistant varieties should be planted when possible. Insecticides should be selected and applied when bugs are small and first appear. Repeated applications are often needed.
Striped Flea Beetle top
Striped flea beetle, Phyllotreta striolata (Fab.), together with other flea beetles, are common pests of collards, turnips, and other greens. Adult beetles are black, measure less than 1/4 inch long, and have a wavy yellow line on each wing. Other flea beetles are entirely black. They have thickened hind legs that allow them to jump when disturbed.
Suggested Management: Cultural practices and the use of resistant varieties help prevent flea beetle infestations. Row covers physically protect seedbeds from these insects. Good weed control and the destruction of crop residue reduce overwintering populations. Planting resistant varieties may also help. Apply chemical treatments as needed.
Turnip Aphid top
The turnip aphid, Lipophis erysimi (K.), is a troublesome pest. Aphids cluster on the underside of leaves and suck sap, causing the foliage to curl, wilt, or become distorted. Plants may be killed or rendered unmarketable. Aphids are pale green and have cornices, or points, on the abdomen.
Suggested Management: Cultural practices and the use of resistant varieties help prevent cabbage aphid infestations. Row covers physically protect seedbeds from these insects. Good weed control and the destrunction of crop residue reduce overwintereing populations. Planting resistant varieties may also help. Apply chemical treatments as needed.
Variegated Cutworm top
Peridroma saucia (Hubner).
Suggested Management: In small gardens, barriers around plants can prevent serious cutworm damage. By encircling individual plants with cardboard or metal collars pressed into the soil, cutworms are barricaded from the plants. This prevention method, however, is not practical for large acreages. Therefore, apply timely sprays as needed.
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