Flora of North America Editorial Committee, Flora of North America 26. 2002
Based on data from the cited flora, not on its key.
1Leaves 80-200 x 15-25 cm; its teeth 5-10 mm long, 1-4 cm apart; flowers 7-10,5 cm long
1'Leaves 90-130 x 9-12 cm; its teeth, if present, 1-2 mm long, 2-5+ cm apart; flowers 5.5-6.5 cm long