Rhizomatous perennial, 3-10 dm, glabrous or subglabrous (often glandular), the lvs often hirsute along the main veins beneath; lvs sessile or subsessile, lance-ovate or elliptic, 3-7 נ0.8-2.5 cm, 2-3.5 times as long as wide, serrate, ±acute; fls crowded into slender terminal spikes (sometimes interrupted below) 3-12 cm long and 0.5-1 cm thick at anthesis; cal 1-3 mm, the lobes generally hispid-ciliate, the tube without hairs; cor 2-4 mm; 2n=48. Banks of streams and ditches, and other moist places; native of Europe, now widely established in N. Amer. and throughout our range.
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.
Martin and Hutchins 1980, Welsh et al. 1993, Kearney and Peebles 1969
Duration: Perennial Nativity: Non-Native Lifeform: Forb/Herb General: Upright perennial from leafy-bracteate stolons, the stems to 1 m or more, usually branched, glabrous or glabrate. Leaves: Sessile or subsessile, blades 2-8 cm long, 0.6-2.5 cm wide, lanceolate to lance oblong, elliptic to ovate, unequally serrate with an acute apex, rounded at base, glandular-punctate. Flowers: Terminal clusters or spikes to 8 cm long, lower glomerules separated, floral bracts glabrous, slender, calyx 1.5-2 mm long, tube glandular, ciliate on margins of the subulate teeth, corolla pink to white, 3-4 mm long. Fruits: Smooth nutlets. Ecology: Found along streams in wet soils from 4,000-6,000 ft (1219-1829 m); flowers June-October. Distribution: Introduced to every state in the U.S. except ND; south to S. Amer.; throughout the world on every continent. Notes: A common introductee to wetlands and streams, distinguished by forming dense stands due to extensive, long rhizomes; oblong, glabrous leaves; and flowers in terminal spikes as opposed to axillary clusters in M. arvensis and as opposed to the villous foliage of M. rotundifolia. Ethnobotany: Taken for headaches, vomiting, as a cold remedy, for fevers, upset stomach, as a sedative, for diarrhea, as a medicine against worms, and used to flavor food, and made into tea. Etymology: Mentha is the Latin name for the unfortunate Greek nymph Mentha who was turned into a mint plant, while spicata means with flowers in spikes. Synonyms: Mentha cordifolia, M. longifolia, M. viridis Editor: SBuckley 2010, FSCoburn 2015
From Flora of Indiana (1940) by Charles C. Deam
This plant was cultivated by the pioneers for its medicinal properties and has escaped in many parts of the state. It is generally found in wet places along roadsides and streams, and about lakes.
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Indiana Coefficient of Conservatism: C = null, non-native