Northern Prairie Wildlife Research Center
Lime green, with continuous dorsal blue-green and brown saddle, extending downward toward second abdominal proleg. Saddle outlined with yellow. Rear of second thoracic segment with raised transverse ridge. Tails (anal prolegs) with extrusible portion brown with pale subapical band. Food: willows and poplars. Caterpillar: June to September; 2 generations.