Herbs, perennial, 2--9 dm. Rhizomes long- creeping. Cataphylls 1--3. Leaves basal, (1--)2--4; auricles 0.4--0.6(--0.8) mm, scarious; blade flat or somewhat channeled,,10--40 cm x 0.4--0.7 mm, margins entire. Inflorescences 10--30(--80)-flowered, usually loose and somewhat lax, 2--16 cm; primary bract rarely surpassing inflorescence. Flowers: bracteoles 2; tepals dark brown or blackish, lanceolate-ovate to oblong, 2.6--3.2(--3.8) mm; inner and outer series nearly equal, apex obtuse; stamens 6, filaments 0.4--0.7 mm, anthers 1.1--1.6(--1.8) mm; style 0.4 mm. Capsules chestnut brown or brown, 3-locular, widely ellipsoid, (2.2--)2.5--3.2(--3.5) x 1.3 -- 1.9 mm. Seeds dark brown, ellipsoid to lunate, 0.485--0.6(--0.67) mm, not tailed. 2n = ca. 80, 84. Flowering and fruiting late spring--summer. Forming extensive colonies in exposed coastal estuary meadows and salt marshes just above high- tide line; also inland; Greenland; St. Pierre and Miquelon; B.C., Man., N.B., Nfld. and Labr. (Nfld.), N.S., Ont., Oreg., P.E.I., Que.; Colo., Conn., Del., Ill., Ind., Kans., Ky., Maine, Md., Mass., Mich., Minn., Mo., N.H., Mont., N.J., N.Y., N.Dak., Ohio, Oreg., Pa., R.I., Utah, Vt., Va., Wash., Wis.; Europe; Asia.
From Flora of Indiana (1940) by Charles C. Deam
A Coastal Plain species which Mr. C. M. Ek found established in Howard County. He reports a colony about 5 by 10 feet (July 20, 1935) on dry open ground along the Nickle Plate Railway 4 miles east of Kokomo. It is doubtless introduced here. In the "Flora of the Indiana Dunes" by Peattie the species is reported from Lake County but no specimens could be found.
Indiana Coefficient of Conservatism: C =null, non-native
Stems 2-6 dm, from long, slender rhizomes; lvs elongate, to 2 dm; cauline lvs 1 or 2, the uppermost divergent near the middle of the stem; lf-sheaths entire at the summit; infl 2-8 cm, many-fld, with ascending or erect branches, seldom surpassed by the invol lf; fls prophyllate; tep oblong, purple-brown with green midstrip, the sep 2.4-3.2 mm, narrowed to an obtuse incurved tip, the pet slightly shorter, scarious at the broad obtuse summit; stamens 6, reaching nearly to the tip of the tep, the anthers ca 1.5 mm, 3-4 times as long as the filaments; fr trilocular, ovoid-ellipsoid, 2.4-3.3 mm, rounded above and short-beaked, equaling or barely surpassing the sep; seeds ca 0.5 mm, ellipsoid or obovoid-ellipsoid, longitudinally ribbed; 2n=80, 84. Salt-marshes along the coast; interruptedly circumboreal, s. to Va.; now widely intr. inland in our range, in both saline and disturbed nonsaline habitats.
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.