Juncus dubius |
Juncus brachycephalus |
|
---|---|---|
dubius rush, mariposa rush, questionable rush |
small-head rush |
|
Habit | Herbs, perennial, rhizomatous, 3–7.5 dm. | Herbs, perennial, cespitose, 2–7 dm. |
Rhizomes | 2–3 mm diam., not swollen. |
|
Culms | erect, terete, 2–4 mm diam., smooth or rugulose. |
erect, 1–4 mm diam., smooth. |
Cataphylls | 1–2, pink to straw-colored, apex acute. |
1–2, straw-colored to pink, apex acute. |
Leaves | basal 1–2, cauline 1–2; auricles 1–4.9 mm, , apex rounded, membranaceous; blade green to straw-colored, terete, 20–30 cm × 1.5–4 mm, rugulose or smooth. |
basal 1–3, cauline 1–2; auricles 0.6–1.5 mm, apex rounded, scarious; blade terete to compressed, 0.2–12 cm × 0.5–2 mm. |
Inflorescences | terminal panicles of 25–66 heads, 7–13 cm, branches spreading; primary bract erect; heads 6–10-flowered, hemispheric to obovoid, 5–10 mm diam. |
panicles of 5–80 heads, 5–25 cm, branches ascending; primary bract erect; heads 2–6-flowered, ellipsoid to obovoid, 2–5 mm diam. |
Flowers | tepals straw-colored to brown, lanceolate, apex acuminate; outer tepals (2–)2.5–3.4 mm; inner tepals (2–)2.6–3.6 mm; stamens 6, anthers 1.5–2 times filament length. |
tepals green to light brown, lanceolate; outer tepals 1.8–2.5 mm, apex obtuse to nearly acute; inner tepals 2–2.8 mm, apex obtuse to nearly acute; stamens 3 or 6, anthers 1/2 filament length. |
Capsules | exserted, chestnut brown, 1-locular, subuloidsubulate, (2.4–)3–3.9 mm, apex tapering to subulate tip, valves separating at dehiscence. |
exserted, chestnut to dark brown, imperfectly 3-locular, obconic, 2.4–3.8 mm, apex acute proximal to beak, valves separating at dehiscence. |
Seeds | obovoid, 0.3–0.4 mm, not tailed. |
ellipsoid to fusiform, 0.8–1.2 mm, tailed; body covered with whitish translucent veil. |
2n | = 40. |
= 80. |
Juncus dubius |
Juncus brachycephalus |
|
Phenology | Fruiting early summer–late fall. | Fruiting summer–early fall. |
Habitat | Montane meadows, riverbeds, canyons, aroyos | Calcareous marshes, wet meadows, and wetland shores |
Elevation | 100–1600 m (300–5200 ft) | 100–200 m (300–700 ft) |
Distribution |
CA
|
AL; CO; CT; GA; IL; IN; MA; ME; MI; MN; NC; ND; NH; NJ; NY; OH; OK; PA; TN; VA; VT; WI; WV; NB; NS; ON; QC;
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Discussion | Juncus dubius has rugulose stems and leaves throughout most of its range, but on the periphery (in Mariposa, San Diego, and Sonoma counties, California) the plants are smooth. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
|
Source | FNA vol. 22. | FNA vol. 22. |
Parent taxa | ||
Sibling taxa | ||
Synonyms | J. rugulosus | J. canadensis var. brachycephalus |
Name authority | Engelmann | (Engelmann) Buchenau: Botanische Jahrbucher fur Systematik, Pflanzengeschichte und Pflanzengeographie 12: 268. (1890) |
Web links |