Juncus brachycephalus |
Juncus subtilis |
|
---|---|---|
small-head rush |
creeping rush, greater creeping rush, jonc délié |
|
Habit | Herbs, perennial, cespitose, 2–7 dm. | Herbs, perennial, emergent, rhizomatous (forming mats to 5 dm), 0.5–1 dm. |
Rhizomes | 1 mm diam., nodes not swollen. |
|
Culms | erect, 1–4 mm diam., smooth. |
repent, floating or submersed, usually profusely branched, terete, 0.5–1 mm diam. |
Cataphylls | 1–2, straw-colored to pink, apex acute. |
absent. |
Leaves | 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. |
basal 1–5, cauline 1–4, small fascicles of short capillary leaves often on rhizomes and stems; auricles 0.1–0.8 mm, apex acute, membranaceous; blade terete, 1.6–3 cm × 0.1–0.3 mm. |
Inflorescences | panicles of 5–80 heads, 5–25 cm, branches ascending; primary bract erect; heads 2–6-flowered, ellipsoid to obovoid, 2–5 mm diam. |
cymes, flowers 1–3 at 1–2 nodes, 1–4 cm, branches spreading to erect. |
Flowers | 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. |
tepals reddish, oblong; outer tepals 1.8–2.8 mm, obtuse; inner tepals 2.2–4.4 mm, obtuse; stamens 6, anthers 3/4 to equal filament length. |
Capsules | exserted, chestnut to dark brown, imperfectly 3-locular, obconic, 2.4–3.8 mm, apex acute proximal to beak, valves separating at dehiscence. |
exserted, chestnut brown, 1-locular, ovoid to narrowly ovoid, 2.4–5 mm, apex acute proximal to beak, valves separating at dehiscence. |
Seeds | ellipsoid to fusiform, 0.8–1.2 mm, tailed; body covered with whitish translucent veil. |
ovoid, 0.3–0.5 mm, not tailed; body clear yellow-brown. |
2n | = 80. |
= 40. |
Juncus brachycephalus |
Juncus subtilis |
|
Phenology | Fruiting summer–early fall. | Fruiting late summer–early fall. |
Habitat | Calcareous marshes, wet meadows, and wetland shores | Muddy, sandy or gravelly shores, fens in decomposed peat, fine muds rich in humus, and submersed in brackish pools |
Elevation | 100–200 m (300–700 ft) | 0–200 m (0–700 ft) |
Distribution |
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;
|
ME; NB; NL; ON; QC; Greenland |
Discussion | Flowers are rarely replaced by bulbils. Most Greenland collections are sterile. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
|
Source | FNA vol. 22. | FNA vol. 22, p. 245. |
Parent taxa | Juncaceae > Juncus > subg. Septati | Juncaceae > Juncus > subg. Septati |
Sibling taxa | ||
Synonyms | J. canadensis var. brachycephalus | J. uliginosus var. subtilis, J. pelocarpus var. subtilis, J. pelocarpus var. fluitans |
Name authority | (Engelmann) Buchenau: Botanische Jahrbucher fur Systematik, Pflanzengeschichte und Pflanzengeographie 12: 268. (1890) | E. Meyer: Syn. Luzul. 31. (1823) |
Web links |