Semi-spherical egg, yellowish-white at first, then pinkish. Eggs have a diameter of 0.7-0.8 mm and a height of 0.4 mm.
Caterpillars are light yellow to fleshy-red in color, with a reddish stripe running down the center of the dorsum. Thoracic and anal shields and plates carrying setae are brown, and the head is crimson with no pattern. Black spiracles 40-45 mm long caterpillars.
Yellow-brown pupae, 17-25 mm long; cremaster with two processes. Although eggs do not overwinter, there is evidence of early instar caterpillars overwintering.
Territory:
The species is distributed in all European parts and North America
Damage caused by Potato Stem Borer:
Damage from noctuids spreading from fence-rows was reduced by burning grasses to destroy eggs or limiting larvae from the crop with mechanical barriers (made of plastic lawn-edging). Double planting such places partially mitigated seedling loss in border rows.
Life history and Habits:
The moth’s forewings are greyish-yellow or dark brown-gray with a reddish hue (28-40 mm). Brown transversal lines: A wing section is darker than the rest, particularly behind round and reniform patches with background wing color. Grayish-yellow or pinkish-yellow hind wings with a black band in the distal part of the wing. Males are often bigger than females. Females deposit eggs in 2-3 rows, in clusters of 20-60 eggs, under leaf axils, and on the bottom sections of stalks of host plants. Caterpillars pupate in underground cocoons.
