Herbs, perennial, rhizomatous, usually fresh-water habitats. Stems terete. Leaves basal or cauline; blade terete, channeled, imperfectly septate or not. Inflorescences terminal panicles or racemes of several heads or a single terminal head, sympodial or monopodial; bracteoles absent at base of perianth. Flowers in multiflowered heads. Capsules (1–)3-locular. Seeds long tailed, large.

Distribution

n North America, n Europe, n Asia.

Discussion

Species 724 (4 in the flora).

Selected References

None.

Lower Taxa

Juncus biglumis, Juncus castaneus, Juncus stygius, Juncus triglumis

Key

1	Plants strongly rhizomatous	Juncus castaneus
1	Plants cespitose, rhizomes (if present) short, sparingly branched.	> 2
2	Leaves basal and cauline	Juncus stygius var. americanus
2	Leaves all basal.	> 3
3	Primary bract of infloresence much longer than inflorescence	Juncus biglumis
3	Primary bract of inflorescence nearly equal to or shorter than inflorescence	Juncus triglumis