Juncus dubius |
Juncus xiphioides |
|
---|---|---|
dubius rush, mariposa rush, questionable rush |
iris-leaf rush |
|
Habit | Herbs, perennial, rhizomatous, 3–7.5 dm. | Herbs, perennial, rhizomatous, 5–9 dm. |
Rhizomes | 2–3 mm diam., not swollen. |
2–3 mm diam. |
Culms | erect, terete, 2–4 mm diam., smooth or rugulose. |
erect, 2–6 mm diam. |
Cataphylls | 1–2, pink to straw-colored, apex acute. |
0 or 1–2, straw-colored, apex narrowly 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 2–6, straw-colored; auricles absent; blade 10–40 cm x (3–)7–12 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 or racemes of 20–50 heads, 2–14 cm, erect or ascending branches; primary bract erect; heads 15–70-flowered, obovoid to globose, 7–11 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 brown or reddish brown, lanceolate, 2.4–3.7 mm, nearly equal, apex acuminate; stamens 6; anthers ½1/2 to equal filament length. |
Capsules | exserted, chestnut brown, 1-locular, subuloidsubulate, (2.4–)3–3.9 mm, apex tapering to subulate tip, valves separating at dehiscence. |
slightly exserted, chestnut to dark brown, 1-locular, ellipsoid, 2.4–3.8 mm, apex acuminate, not beaked. |
Seeds | obovoid, 0.3–0.4 mm, not tailed. |
elliptic to obovate, 0.4–0.6 mm, not tailed. |
2n | = 40. |
= 40. |
Juncus dubius |
Juncus xiphioides |
|
Phenology | Fruiting early summer–late fall. | Fruiting early summer–fall. |
Habitat | Montane meadows, riverbeds, canyons, aroyos | Salt marshes, moist areas, ditches, springs, lake and stream shores |
Elevation | 100–1600 m (300–5200 ft) | 500–1600 m (1600–5200 ft) |
Distribution |
CA
|
AZ; CA; NM; NV; UT; Mexico (Baja California)
|
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.) |
This species and the next (Juncus ensifolius) are closely related and have been treated as members of a single species (J. xiphioides) by Engelmann. Until a study of the complete subgenus is done, we are hesitant to use a varietal name (J. xiphioides var. triandrus) for the widespread western taxon J. ensifolius. (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. xiphioides var. auratus, J. xiphioides var. littoralis |
Name authority | Engelmann | E. Meyer: Synopsis Juncorum 50. (1822) |
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