Juncus dubius |
Juncus trifidus |
|
---|---|---|
dubius rush, mariposa rush, questionable rush |
highland rush |
|
Habit | Herbs, perennial, rhizomatous, 3–7.5 dm. | Herbs, perennial, tufted, 1–4 dm. |
Rhizomes | 2–3 mm diam., not swollen. |
densely branching. |
Culms | erect, terete, 2–4 mm diam., smooth or rugulose. |
few to many, erect to drooping. |
Cataphylls | 1–2, pink to straw-colored, apex acute. |
2–4. |
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 and cauline, 2–4; auricles deeply lacerate, to 4 mm, membranous; blade dark green, flat to slightly channeled, 5–12 cm × 0.5–1 mm, margins finely serrulate. |
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. |
1–3(–4)-flowered; primary bract usually exceeding 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, usually lacerate; tepals brownish, widely lanceolate, 2.1–3 mm; inner series slightly shorter, apex acute; stamens 6, filaments 0.3–0.7 mm, anthers 1.2–1.5 mm; stigma 1.5–3 mm. |
Capsules | exserted, chestnut brown, 1-locular, subuloidsubulate, (2.4–)3–3.9 mm, apex tapering to subulate tip, valves separating at dehiscence. |
brown, ellipsoid, 2.2–3.5 × 1.3–1.7 mm, longer than tepals. |
Seeds | obovoid, 0.3–0.4 mm, not tailed. |
brown, obliquely ovoid, 0.89–1.35 mm, not tailed. |
2n | = 40. |
= 40. |
Juncus dubius |
Juncus trifidus |
|
Phenology | Fruiting early summer–late fall. | Flowering and fruiting late spring–early summer. |
Habitat | Montane meadows, riverbeds, canyons, aroyos | Mostly in crevices of granitic (schistose) cliffs or rubble slopes in the higher regions of the Appalachians |
Elevation | 100–1600 m (300–5200 ft) | 20–2000 m (100–6600 ft) |
Distribution |
CA
|
ME; NC; NH; NY; TN; VA; VT; NB; NL; NS; QC; Greenland; Europe; n Asia |
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. monanthos, J. trifidus subsp. carolinianus, J. trifidus subsp. monanthos, J. trifidus var. monanthos |
Name authority | Engelmann | Linnaeus: Sp. Pl. 1: 326. (1753) |
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