Juncus nodosus L.

The Texas populations and some of the northern Mexican populations consistantly have 3 stamens. These populations have been separated as Juncus nodosus var. meridionalis. Plants with 3 stamens are found elsewhere, however, and other significant characters do not appear to separate these populations.

Herbs, perennial, rhizomatous, 0.4--5.5(--7) dm. Rhizomes with swollen nodes, 1 mm diam. Culms erect, terete, 1--3 mm diam., smooth. Cataphylls 0 or 1--2., pink to gray, apex acute. Leaves: basal 1, cauline 2--4, green to pink; auricles 0.5--1.7 mm, apex rounded, membranaceous to cartilaginous; blade terete, 6--30 cm x 0.5--1.5 mm. Inflorescences terminal racemes of 3--15 heads, 0.6--6 cm, branches ascending to erect; primary bract erect; heads 6--30-flowered, spheric, 6--10(--12) mm diam. Flowers: tepals green to light brown, lance-subulate, 2.4--4.1 mm, nearly equal, apex acuminate; stamens 3 or 6, anthers 1/2 to equal filament length. Capsules exserted, chestnut brown, 1-locular, lance-subulate, 3.2--5 mm, apex tapering, valves separating at dehiscence, fertile throughout or only proximal to middle. Seeds oblong, ellipsoid, or obovoid, 0.4--0.5 mm, not tailed. . 2n = 40.

Alta., B.C., Man., N.B., Nfld. and Labr., N.W.T., N.S., Ont., P.E.I., Que., Sask., Yukon; Alaska, Ariz., Calif., Colo., Conn., Del., Idaho, Ill., Ind., Iowa, Kans., Maine, Md., Mass., Mich., Minn., Mo., Mont., Nebr., Nev., N.H., N.J., N.Mex., N.Y., N.Dak., Ohio, Okla., Pa., R.I., S.Dak., Tex., Utah, Vt., Va., Wash., W.Va., Wis., Wyo.; Mexico (s to Puebla).

Fruiting early summer--fall.

Sandy and muddy shores of lakes, streams, rivers, and estuaries (both freshwater and brackish), swamps, fens, salt marshes, and wet fields, often calcareous; 0--2200m.

Juncus nodosus var. meridionalis F. J. Hermann; J. rostkovii E. Meyer

Juncus nodosus is a species of rush known by the common name knotted rush. It is native to much of North America from northern Canada to central Mexico, where it grows in wet places from freshwater to salt marsh habitat. This is a rhizomatous perennial herb producing slender, smooth stems up to about 60 centimeters tall. The inflorescence is a series of spherical clusters of flowers. Each flower has green or brown pointed segments each a few millimeters long and tapering to a point.

Juncus nodosus là một loài thực vật có hoa trong họ Juncaceae. Loài này được L. mô tả khoa học đầu tiên năm 1762.