The plant grows from rhizomes that measure 30 cm or longer, and 2.5 to 5 cm in diameter. The leaves are the largest of any native plant in the region, 50–135 cm long and 30–80 cm wide when mature. Its flowers are produced in a spadix contained within a large, bright yellow or yellowish green spathe 30–40 cm tall; it is among the first flowers to appear in spring.[3] Unlike the genus Symplocarpus (which includes S. foetidus, the eastern skunk cabbage), the flowers of Lysichiton species do not produce heat,[4] although this is widely and incorrectly said to be the case.