21 February 2021

A robust perennial plant with a fibrous root system, forming clumps up to 3 ft (90 cm) tall. The upright squarish stems have small side branches, and send out rhizomes at the base. The leaves are opposite, stemmed lower on the plant and unstemmed on the upper sections of the stalk. They are ovate or lanceolate, deeply veined and coarsely toothed, up to 5 in (13 cm) long and 2.5 in (6 cm) wide. The terminal inflorescence contains numerous whitish or pale lilac lipped flowers with large shelf-like lower lips. The fruits contain four pitted seeds covered with white hairs.

The species is native to North America. Its range extends throughout the 48 contiguous states of the United States, and it is also present in much of Canada. It is a common plant, growing in moist grassland, at the edges of forests, in thickets, on river verges and at the edges of marshes. It also grows on wasteland, in poorly-drained areas and beside roadside ditches, and can be somewhat invasive.