Insect Management Handbook

Gymnocarena diffusa

Pest description and crop damage The adult fly is 0.5 inch in length: eyes are bright green and wings have a yellow-brown mottle. Significant yield losses have not been demonstrated for this insect and treatment is generally not considered necessary.

Management-chemical control

Zygogramma exclamationis

Black sunflower stem weevil (Apion occidentale)
Sunflower stem weevil (Cylindrocopturus adspersus)

Includes

Gray seed weevil (Smicronyx sordidus)
Red sunflower seed weevil (Smicronyx fulvus)

Several species

Management-chemical control

Includes

Darksided cutworm (Euxoa messoria)
Dingy cutworm (Feltia jaculifera)
Redbacked cutworm (Euxoa ochrogaster)

Cochylis hospes

Sugar beet wireworm (Limonius californicus)
Pacific Coast wireworm (Limonius canus)

Scarabaeidae

Pest description and crop damage Robust, C-shaped larvae of June beetles, 0.125 to 1.25 inches in length, with a brown head capsule and prominent jointed legs. The body is an overall dirty white, but the last abdominal segments are blue-black internally. Damage from larval feeding appears as severed (cut) taproots in early season and as surface cavities on taproots later during the season.

Alfalfa webworm (L. cereralis)

Beet webworm (Loxostege sticticalis)
Garden webworm (Achyra rantalis)

Pest description and crop damage Olive-green larvae up to 1.5 inches in length, marked with black dots and both dark and light stripes down the back and along sides. If disturbed, larvae hang from leaves by silk threads.