Juncus subg. Juncus
Herbs, perennial, rhizomatous. Stems terete. Leaves basal; blade terete, not septate. Inflorescences terminal (sometimes appearing lateral) panicles of few to many heads, sympodial; bracteoles absent proximal to perianth. Flowers in few-flowered heads. Capsules 3-locular or pseudo-3-locular. Seeds usually tailed (not tailed in J. roemerianus).
Worldwide, coastal in North America.
Species 9 (4 in the flora).
|1||Capsules 3.5–5 mm; plants of sw United States.||> 2|
|1||Capsules less than 3.5 mm, shorter than or nearly equal to perianth; plants of ne United States Atlantic Coast.||> 3|
|2||Capsules nearly globose, obviously longer than perianth||Juncus acutus subsp. leopoldii|
|2||Capsules ellipsoid, nearly equal to or shorter than perianth||Juncus cooperi|
|3||Capsules nearly equal to perianth; seeds tailed||Juncus maritimus|
|3||Capsules distinctly shorter than perianth; seed not tailed||Juncus roemerianus|