Epilobium

Tutin, T. G., Heywood, V. H., Burges, N. A., Moore, D. M., Valentine, D. H., Walters, S. M. & Webb, D. A., 1981, Flora Europaea. Volume 2. Rosaceae to Umbelliferae, Cambridge University Press : 309

Sect. Epilobium (Sect. Lysimachion Tausch). Roots rather slender. Leaves opposite or verticillate, at least below. Flowers actinomorphic or nearly so; petals emarginate, white, pink or purplish. Stigma 4-lobed (spp. 5-10), or entire. Pollen grains shed in tetrads.

Although self-pollination is normal in most European species of this section, occasional hybrids occur between many of the species, and may best be recognized by their intermediate morphology and (usually) by their high degree of sterility. Most of the species occur on moist or disturbed ground.