10. Juncus diffusissimus Buckley (slimpod rush)

Pl. 94 l, m; Map 367

Aerial stems 20–60 cm tall, caespitose, lacking noticeable rhizomes. Leaves with the auricles at the top of the sheaths 1–2 mm long, papery, broadly pointed, the leaf blades 4–20 cm long, 3–5 mm wide, tubular and hollow, circular in cross-section, with cross-partitions at regular intervals. Basal leaves few, usually 1 or 2 of them lacking a leaf blade. Leaves of the aerial stems 1–4. Inflorescences diffuse panicles, the branches ascending to spreading, the leaflike bract at the base shorter than the inflorescence. Flower clusters 30–200 or more per inflorescence, mostly wedge-shaped, each with 3–10 flowers. Flowers lacking a pair of closely subtending bracts. Perianth 2.3–2.8 mm long, the sepals about as long as the petals, linear-lanceolate, the tips acuminate. Stamens 3 per flower. Fruits 4–6 mm long, about twice as long as the perianth, linear to linear-lanceolate in outline, the tip long-tapered, 1-locular. Seeds 0.4–0.5 mm long, both ends with short, dark points. May–September.

Scattered south of the Missouri River (southeastern U.S. north to Oklahoma and West Virginia). Fens, stream banks, margins of ponds, lakes, and sloughs, and disturbed, moist, open areas.