Identification
Adult: forewing pale yellowish to light brown with sharp median and PM lines; ring-like marking in upper median area resembles a tied knot (a diagnostic feature); hindwing light gray with dark terminal band and partial PM line
Range
Newfoundland west across Canada, south to Colorado, east to Virginia and Maryland
also occurs in Europe and western Asia
Season
adults fly from May to September
larvae present in August and September
Food
larvae feed on bittercress, cabbage, radish, horseradish, turnip, and other plants in the mustard family
See Also
no similar species: the ring-like "tied knot" marking on the forewing is diagnostic
Internet References
live adult images plus description, foodplants, flight dates (Lynn Scott, Ontario)
live and pinned adult images by various photographers (Moth Photographers Group)
live adult image (Larry Line, Maryland)
pinned adult image (David Smith, Furman U., South Carolina)
pinned adult image (Bert Gustafsson, Swedish Museum of Natural History)
pinned adult image (James Adams, Dalton State College, Georgia)
common name reference plus foodplants and flight season (Ohio State U.)
