Juncus laccatus
Bruce N. Newhouse

Flora of Oregon

Plants perennial, 25–108 cm tall, cespitose, fresh stems shiny, smooth, dried fruiting stems slender, 0.6–2.6 mm diameter above distal sheath, remaining green, with 6–16 strong ridges becoming visible per side, dried ridges coarse or wide, capped with low dull cells.

Leaves lacking blades; proximal sheaths smooth, not papillose (at 10×); distal sheaths 5–18 cm, distal half dark brown or black, shiny, thick and glossy, nerves obscure, apices symmetrical, unwinged, uniformly thick, dark, not inrolled.

Inflorescences loose clusters, branches usually visible, inflorescence bracts not swollen.

Flowers tepals 6, medium to dark brown-striped; stamens 3, filaments 0.4–0.9 mm, anthers 0.4–0.9 mm; styles 0.05–0.3 mm.

Capsules 1.7–2.2 mm, shorter than the tepals, brown to dark brown, apex obtuse to acute, 1-chambered.

Seeds 0.4–0.6 × 0.2–0.25 mm, reticulate, apiculate.

2n=40, 80.

Shores, swales, springs, seasonally wet ground, peatlands, and ditches. 0–1600m. Casc, CR, Est, WV. CA, WA; north to British Columbia, southeast to Arizona. Native.

Occasionally cultivated, the thick shiny dark and smooth sheath of this species is distinctive; J. exiguus has a thinner, paler, and more textured sheath; J. hesperius has a less shiny, paler, and papillose sheath.

Photo images

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Herbarium specimens

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