National Geographic : 1957 Apr
© National (;oiraphic Society 529 Fireweed, the Temperate Zone's Four-foot Giant, Becomes the Arctic's Four-inch Pygmy Plants of the living Ice Age tend to remain small owing to lack of water and soil and the fierce intensity of the Arctic sun, which in summer shines around the clock. Showiest of northern flowers, this fireweed, Epilobium latifolium, grows above fossils of one of the world's earliest known deciduous forests, near D)isko Island, Greenland. Its ancestral forms may have marched north out of Ice Age America behind retreating glaciers. Fireweed is so named because it often springs up in ruins left by fire.