Juncus dubius |
Juncus georgianus |
|
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dubius rush, mariposa rush, questionable rush |
Georgia rush |
|
Habit | Herbs, perennial, rhizomatous, 3–7.5 dm. | Herbs, short-lived perennial, cespitose, to 4 dm. |
Rhizomes | 2–3 mm diam., not swollen. |
|
Culms | erect, terete, 2–4 mm diam., smooth or rugulose. |
3–40. |
Cataphylls | 1–2, pink to straw-colored, apex acute. |
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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, 2–3; auricles 0.2–0.3 mm, scarious to membranous; blade flat, 5–15 cm × 0.4–0.7 mm, margins entire. |
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. |
(3–)8–30(–45)-flowered, diffuse, 3–11 cm; primary bract rarely surpassing inflorescence. |
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. |
bracteoles 2; tepals greenish to tan, lanceolate, (3.3–)3.6–5.1(–5.7) mm; outer and inner series nearly equal, apex acuminate; stamens 6, filaments 0.2–0.4 mm, anthers (0.8–)1.2–1.5(–1.7) mm; style 0.6–0.8 mm. |
Capsules | exserted, chestnut brown, 1-locular, subuloidsubulate, (2.4–)3–3.9 mm, apex tapering to subulate tip, valves separating at dehiscence. |
tan, 3-locular, ellipsoid to narrowly so, 2.7–4 × 1.2–1.7 mm. |
Seeds | obovoid, 0.3–0.4 mm, not tailed. |
tan, ellipsoid or widely so, 0.364–0.45 mm, not tailed. |
2n | = 40. |
= ca. 80. |
Juncus dubius |
Juncus georgianus |
|
Phenology | Fruiting early summer–late fall. | Flowering and fruiting spring. |
Habitat | Montane meadows, riverbeds, canyons, aroyos | Exposed sites with thin, usually sandy soil over surfacing granite (flatrocks), the soil in these areas may be moist in the spring from seepage or for a short period after rainfalls |
Elevation | 100–1600 m (300–5200 ft) | 300–600 m (1000–2000 ft) |
Distribution |
CA
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AL; GA; NC; SC |
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.) |
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Source | FNA vol. 22. | FNA vol. 22. |
Parent taxa | ||
Sibling taxa | ||
Synonyms | J. rugulosus | |
Name authority | Engelmann | Coville: Bulletin of the Torrey Botanical Club 22:44. (1895) |
Web links |