. Cooperative economic insect report. Beneficial insects; Insect pests. 498 Hosts: Attacks many plants. The most important cultivated hosts are potatoes, beets, flax, hemp, crucifers and legumes. Cereals, grasses and even forest trees, are sometimes attacked. Life History and Habits: The adults appear during June. Females oviposit about 500 whitish eggs, singly or in small batches, on the underside of leaves of low-growing plants. The incubation period lasts for 10-12 days. The young caterpillars web and feed on vegetation of the host plants. At times the larvae may destroy entire crops during
. Cooperative economic insect report. Beneficial insects; Insect pests. 498 Hosts: Attacks many plants. The most important cultivated hosts are potatoes, beets, flax, hemp, crucifers and legumes. Cereals, grasses and even forest trees, are sometimes attacked. Life History and Habits: The adults appear during June. Females oviposit about 500 whitish eggs, singly or in small batches, on the underside of leaves of low-growing plants. The incubation period lasts for 10-12 days. The young caterpillars web and feed on vegetation of the host plants. At times the larvae may destroy entire crops during outbreaks, then collect in great numbers on the soil and migrate in bands to other fields, devouring suscep- tible foliage in their path. The larvae readily drop from plants when disturbed. Larval development requires less than a month. By July, most of the feeding is completed and toward the end of the month pupation occurs. Pupation takes place in a cocoon on host plants and lasts from 12 to 15 days. Second-brood adults are in flight from mid-August to mid-September. Second- brood larvae develop to late instars or into pupae before hibernation. There are normally two generations a year. Description: Adult forewings are marbled in appearance, ground color is silvery-gray to reddish-gray with a velvety sheen. The Y mark is distinct and silvery; hindwings brownish with a darker border. Wing expanse is 36 to 40 mm. Larva is of varying shades of green, with a dark green dorsal line and a paler line of whitish-green on each side. Spiracular line yellowish edged above with green. Some larval forms have a number of white spots. Head with black markings. The larva of this species cannot be separated from larvae of several other species of the group that occur in the United States without a technical description. The cocoon is dirty-white. (Prepared in Plant Pest Survey Section in cooperation with other ARS agencies.) CEIR 8(23) 6-6-58. Adult of Autographa gamma Adult from Furneaux, W
Size: 2056px × 1216px
Photo credit: © The Book Worm / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1900, booksubjectbeneficialinsects, booksubjectinsect
