Juncus tenuis

Willdenow

Sp. Pl. 2(1): 214. 1799.

Common names: Path rush
WeedyIllustrated
Synonyms: Juncus bicornis Michaux Juncus bicornis var. williamsii (Fernald) Victorin Juncus macer forma williamsii (Fernald) F. J. Hermann Juncus macer Juncus macer var. williamsii (Fernald) Fernald Juncus tenuis var. bicornis (Michaux) E. Meyer Juncus tenuis var. multicornis E. Meyer Juncus tenuis var. williamsii Fernald
Treatment appears in FNA Volume 22.

Herbs, perennial, tufted, 1.5–5 dm. Rhizomes densely branching. Culms few–20. Leaves basal, (1–)2–3; auricles 2–5 mm, apex acute, membranous; blade flat, 3–12 cm × 0.5–1 mm, margins entire. Inflorescences 5–40-flowered, borne congested or branch internodes ca. as long as tepals, ssomewhat loose, 1–5 cm; primary bract usually longer than inflorescence. Flowers: bracteoles 2; tepals greenish, lanceolate, 3.3–4.4 mm; outer and inner series nearly equal; stamens 6, filaments 0.5–0.9 mm, anthers 0.1–0.2 mm; style 0.1–0.2 mm. Capsules tan or light brown, 1-locular to pseudo-3-locular, ellipsoid, (3.3–)3.8–4.7 × (1.1–)1.3–1.7 mm, nearly equal to tepals. Seeds tan, ellipsoid to lunate, (0.52–)5.5–0.65(–0.7) mm, not tailed. 2n = 80.


Phenology: Flowering spring–early summer.
Habitat: Exposed or shaded sites in soils ranging from sandy to clayey under moist or drier conditions, oftentimes these sites naturally or otherwise disturbed (e.g., game or human trails)

Distribution

V22 481-distribution-map.jpg

Alta., B.C., Man., N.B., N.S., Ont., P.E.I., Que., Sask., Ala., Alaska, Ariz., Ark., Calif., Colo., Conn., Del., D.C., Fla., Ga., Idaho, Ill., Ind., Iowa, Kans., Ky., La., Maine, Md., Mass., Mich., Minn., Miss., Mo., Mont., Nebr., Nev., N.H., N.J., N.Mex., N.Y., N.C., N.Dak., Ohio, Okla., Oreg., Pa., R.I., S.C., S.Dak., Tenn., Tex., Utah, Vt., Va., Wash., W.Va., Wis., Wyo., introduced worldwide.

Discussion

Juncus tenuis occurs throughout North America. It is particularly abundant in northeastern United States and eastern Canada, although infrequent in the south and west.

Through the use of isozyme electrophoresis, hybridization can be demonstrated between various members of the Juncus tenuis complex, including Juncus tenuis, J. anthelatus, J. interior, J. secundus, and J. dichotomus (R. E. Brooks, unpubl.). Juncus ××oronensis is thought to be a hybrid between J. tenuis and J. vaseyi in the northeast.

Selected References

None.

Lower Taxa

None.
... more about "Juncus tenuis"
Ralph E. Brooks* +  and Steven E. Clemants* +
Willdenow +
Path rush +
Alta. +, B.C. +, Man. +, N.B. +, N.S. +, Ont. +, P.E.I. +, Que. +, Sask. +, Ala. +, Alaska +, Ariz. +, Ark. +, Calif. +, Colo. +, Conn. +, Del. +, D.C. +, Fla. +, Ga. +, Idaho +, Ill. +, Ind. +, Iowa +, Kans. +, Ky. +, La. +, Maine +, Md. +, Mass. +, Mich. +, Minn. +, Miss. +, Mo. +, Mont. +, Nebr. +, Nev. +, N.H. +, N.J. +, N.Mex. +, N.Y. +, N.C. +, N.Dak. +, Ohio +, Okla. +, Oreg. +, Pa. +, R.I. +, S.C. +, S.Dak. +, Tenn. +, Tex. +, Utah +, Vt. +, Va. +, Wash. +, W.Va. +, Wis. +, Wyo. +  and introduced worldwide. +
Exposed or shaded sites in soils ranging from sandy to clayey under moist or drier conditions, oftentimes these sites naturally or otherwise disturbed (e.g., game or human trails) +
Flowering spring–early summer. +
Weedy +  and Illustrated +
Juncus bicornis +, Juncus bicornis var. williamsii +, Juncus macer +, Juncus macer var. williamsii +, Juncus tenuis var. bicornis +, Juncus tenuis var. multicornis +  and Juncus tenuis var. williamsii +
Juncus tenuis +
Juncus subg. Poiophylli +
species +