AppearanceThis is rhizomatous perennial growing 20 centimeters to well over a meter tall, its 4-angled stem usually erect. The oppositely arranged leaves are lance-shaped to oblong, up to 8 centimeters long, and sometimes joined or nearly so clasping the stem. The herbage is hairless. The flower 2 to 3 centimeters long, its tubular base encapsulated in a ribbed calyx of sepals with pointed lobes. The flower is lavender in color and divided into an upper lip and a larger, swollen lower lip.
StatusOne variety of this plant, var. ''colophilus'', is rare, ecologically restricted, and vulnerable. It is known from Quebec, it has been reported in Vermont, and there are a few occurrences in Maine, where it grows only in freshwater sections of tidal estuaries. This plant variety faces several threats, but its current status is not known due to a lack of data.
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