Genus: Epilobium from Greek epi 'upon' and lobos 'a pod'
Species: angustifolium mean 'narrow-leaved'
aka Willow-herb, Rosebay Willowherb, Chamerion angustifolium. Often the first to emerge in burned or logged over areas. A beautiful but invasive plant spreads by winged seeds and extensive runners. The rose to purple flowers have four petals and are fairly large, 1" or more (2 - 3 cm) across. The genus name, "upon the pod", refers to the inferior ovary where the petals are attached above the ovary. The plant can grow to 6'. Very common in dry open places particularly clearings and disturbed areas below 5,500' elevation (or higher - see 'high flyer'). (ref. Blackwell)