Stems four-angled, 2 to 4 feet high or sometimes taller from a perennial root, smooth or somewhat pubescent or tomentose above and more or less branched. Leaves opposite or sometimes in threes, sessile, lanceolate, clasping and heart-shaped at the base 2 to 3 inches long, one-fourth to one-half of an inch wide. Flowers purple, one-half to two-thirds of an inch long and half as broad, in dense, terminal, branched racemes interspersed with numerous small leaves; petals four or five, usually five; stamens eight or ten, the longer ones scarcely projecting beyond the flower.
Native of Europe but thoroughly naturalized and common in wet places and swamps throughout the east. Very common along the Hudson river from Albany to New York. Flowering in July and August.
Memoir 15 N. Y. State Museum
B. Spiked Or Purple Loosestrife