Coefficient of Conservatism:
Coefficient of Wetness:
A Eurasian species, introduced into North America by the earliest 19th century for its colorful flowers, and now an attractive but persistent invasive weed spreading vigorously in wet ground (see Stuckey 1980, esp. p. 9 for Michigan history). Marshes, shores, borders of rivers and streams, ditches; aggressively crowding out the native wetland flora. Reported by the First Survey (1838), but the oldest Michigan collection located by Stuckey dates from 1879 (Muskegon, Muskegon Co.); almost all other records from the state date from the 1890’s onward.
The rather dense pubescence, especially on the upper part of the plant, will readily distinguish this species from the others, as will the larger and more numerous, hence much more showy, flowers in thick purple spike-like inflorescences. Variable in leaf shape and in pubescence, some plants being more glabrate and/or with narrower leaves than most.