Northern Prairie Wildlife Research Center
Pale green, rarely brown or orangish; white granulose spots arranged in rings around body. Head flattened, triangle pinkish, bounded laterally by pale band from eyes to vertex. Three to 6 midabdominal oblique yellow stripes, most conspicuous on second, third, and fourth segments; each stripe continued back onto adjoining segment. Broader oblique pale stripe extending from prolegs on sixth segment onto shortened horn. Food: poplars. Caterpillar: July through November; 2 generations in South, 1 in North.