Juncus dubius |
Juncus greenei |
|
---|---|---|
dubius rush, mariposa rush, questionable rush |
Greene's rush, jonc de Greene |
|
Habit | Herbs, perennial, rhizomatous, 3–7.5 dm. | Herbs, perennial, tufted, to 7 dm. |
Rhizomes | 2–3 mm diam., not swollen. |
short, densely branched. |
Culms | erect, terete, 2–4 mm diam., smooth or rugulose. |
1–30. |
Cataphylls | 1–2, pink to straw-colored, apex acute. |
1–2. |
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–)2–3; auricles (0.2–)0.4–0.6 (–0.8) mm, scarious, rarely ± leathery; ; blade dark green, nearly terete, 5–30 cm × 0.4–0.8 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. |
terminal, 5–50-flowered, usually congested, 1–8 cm; primary bract usually 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 dark green or darker, lanceolate, 2.5–4.2 mm; outer and inner series nearly equal, apex acute; stamens 6, filaments 0.5–0.8 mm, anthers 0.5–0.8 mm; style 0.2 mm. |
Capsules | exserted, chestnut brown, 1-locular, subuloidsubulate, (2.4–)3–3.9 mm, apex tapering to subulate tip, valves separating at dehiscence. |
chestnut brown or dark brown, infrequently lighter, 3-locular, ellipsoid, (2.5–)2.9–3.5(–4) × (1.1–)1.5–1.8 mm, slightly exceeding tepals, apex somewhat truncate. |
Seeds | obovoid, 0.3–0.4 mm, not tailed. |
dark tan, ellipsoid to lunate, 0.48–0.65–(0.7) mm, not tailed. |
2n | = 40. |
= ca. 80. |
Juncus dubius |
Juncus greenei |
|
Phenology | Fruiting early summer–late fall. | Flowering and fruiting summer. |
Habitat | Montane meadows, riverbeds, canyons, aroyos | Usually dry, well-drained, sandy soil in pine lands, near lake shores, or among sand dunes and often associated with disturbance |
Elevation | 100–1600 m (300–5200 ft) | |
Distribution |
CA
|
CT; IA; IL; IN; MA; ME; MI; MN; NH; NJ; NY; OH; PA; RI; VT; WI; NB; NS; ON; PE; QC
|
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 | |
Name authority | Engelmann | Oakes & Tuckerman: American Journal of Science, and Arts 45:37. (1843) |
Web links |