Leafy Vegetables [South]

armyworm larva

Courtesy of Clemson University –
USDA Cooperative Extension Slide Series,
www.InsectImages.org.

Armyworms (There are many species of armyworm. The following is a description that depicts some armyworm species.)

Armyworm larvae can grow up to 11/4 inches long. They have three lightly colored stripes running the length of their body. Black spots accompany the stripes on the second segment located behind the head.

Larvae pupate at fifth instar and the pupae are about 1/2 to 3/4 inch long. They are light brown with dark brown margins along their abdominal segments.

Forewings of adult armyworms are mottled gray or brown with a pale spot near the center of each wing. Their wingspan is 1/2 to 1 inch long, and the hind wings are white with darker veins and a fringelike border.

The armyworm infects many weeds, trees, grasses, legumes, truck crops and field crops and is attracted to wild hosts such as plantain, lambsquarters and redroot pigweed.

Recommendations
Intrepid ® 2F insecticide, with the active ingredient methoxyfenozide, and SpinTor® 2SC Naturalyte® insect control, with the active ingredient spinosad, are ideal rotational partners in a foliar treatment program with products containing the active ingredient methomyl.



cabbage looper larva

Courtesy of Alton N. Sparks, Jr., University of Georgia,
www.InsectImages.org.
 

Cabbage Loopers
Cabbage looper larvae are green caterpillars with white stripes running the length of their body. Larvae can grow up to 1 1/4 inches long and the body tapers toward the head. There are three pairs of legs near the head, and three pairs of fleshly prolegs near the posterior. The body is humped or “looped” when moving or resting.

After five instars, larvae pupate into a fragile, silken cocoon. Young pupae are a light greenish color that gradually turns dark brown when mature. They grow to 3/4 inch long.

Adult cabbage loopers are mottled, grayish-brown and have a wing span of 1/2 inch, with a small silvery-white figure eight in the middle area of each of the front wings. Forewings have two shades of grey and blackish zig-zag stripes with hind wings being a pale brown in color. Another characteristic is a tuft of hair arising from behind the back of the moth’s head.

Recommendations
Intrepid and SpinTor may be rotated in foliar treatments for control of cabbage loopers. Products with the active ingredient acephate, emamectin benzoate, thiodicarb or zeta-cypermethrin.
cabbage looper adult

Courtesy of Joseph Berger,
www.InsectImages.org.
 



diamondback moth larva

Courtesy of Alton N. Sparks, Jr., University of Georgia,
www.InsectImages.org.
 

Diamondback Moths
The diamondback moth larva is pale yellowish-green to green, and is covered with fine, scattered, erect hairs. Larvae also have a forked posterior. Larvae mature to be cigar-shaped and about 1/2 inch long. After hatching from the egg, larvae burrow into leaf tissue for about a week before exiting to feed externally on the plant. Disturbing the larvae will cause them to actively wriggle or drop from the leaf on a silken thread, which is a distinguishing characteristic.

Pupae develop after four instars into a delicate, loosely spun cocoon. After emergence, adults are about 1/3 inch long. They are slender, grayish-brown moths with folded wings flaring outward and upward at their back end. Males have a row of three diamond-shaped yellow spots along the middle of their back when they fold their forewings.

Recommendations
SpinTor® 2SC Naturalyte® insect control, with the active ingredient spinosad will control diamondback moth and manage insecticide resistance when used in a rotational program with a product containing the active ingredient Bacillus thuringiensis, emamectin benzoate, endosulfan, permethrin or thiodicarb, will control diamondback moth and manage insecticide resistance.
diamondback moth adult

Courtesy of Alton N. Sparks, Jr., University of Georgia,
www.InsectImages.org.
 



vegetable leafminer adults

Courtesy of Whitney Cranshaw,
Colorado State University,
www.InsectImages.org.
 

Leafminers
Coiled mines in leaves with one end slightly enlarged indicate leafminer infestation. The maggot is colorless to bright yellow, and up to 1/8 inch long.

Pupae are flattened, segmented and an oblong-oval in shape. At slightly less than 1/8 inch long, young pupae are bright yellow, but gradually turn brown.

Adults are slender and about 1/8 inch long.

Recommendations
SpinTor applied as a foliar treatment can be rotated in a resistance management program with products containing the active ingredient abamectin or cyromazine.



For a complete IRM fruiting vegetables management guide, visit the Georgia Pest Management Handbook or Insect Control for Commercial Vegetables from North Carolina State University.

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