Juncus brachycephalus |
Juncus occidentalis |
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small-head rush |
prairie rush, slender juncus, western rush |
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Habit | Herbs, perennial, cespitose, 2–7 dm. | Herbs, perennial, cespitose, 3–6 dm. |
Rhizomes | densely branching. |
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Culms | erect, 1–4 mm diam., smooth. |
few–20. |
Cataphylls | 1–2, straw-colored to pink, apex acute. |
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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–)2–3; auricles 0.5–1(–1.5) mm, apex acutish, membranous; blade flat, 5–15 cm × 0.5–1.3 mm, margins entire. |
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. |
5–50-flowered, somewhat loose, 1–7 cm; primary bract usually longer than inflorescence. |
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. |
bracteoles 2; tepals greenish, lanceolate, (3.5–)5 mm; outer and inner series nearly equal; stamens 6, filaments 0.5–1 mm, anthers 0.1–0.3 mm; style 0.1–0.2 mm. |
Capsules | exserted, chestnut to dark brown, imperfectly 3-locular, obconic, 2.4–3.8 mm, apex acute proximal to beak, valves separating at dehiscence. |
light brown, 1-locular to pseudo-3-locular, ellipsoid, (3–)5–4.5 × 1.2–1.8 mm, nearly equal to shorter than tepals. |
Seeds | ellipsoid to fusiform, 0.8–1.2 mm, tailed; body covered with whitish translucent veil. |
tan, ellipsoid to lunate, 5.5–0.7 mm, not tailed. |
2n | = 80. |
= 80. |
Juncus brachycephalus |
Juncus occidentalis |
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Phenology | Fruiting summer–early fall. | Flowering spring–early summer. |
Habitat | Calcareous marshes, wet meadows, and wetland shores | Moist, usually exposed sites in clayey or sandy soil around springs, along rivers and streams, and around lakes |
Elevation | 100–200 m (300–700 ft) | below 2300 m (below 7500 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;
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AZ; CA; ID; NV; OR; WA
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Discussion | Juncus occidentalis should perhaps be considered a robust variant of J. tenuis. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
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Source | FNA vol. 22. | FNA vol. 22. |
Parent taxa | Juncaceae > Juncus > subg. Septati | Juncaceae > Juncus > subg. Poiophylli |
Sibling taxa | ||
Synonyms | J. canadensis var. brachycephalus | J. tenuis var. occidentalis, J. tenuis var. congestus |
Name authority | (Engelmann) Buchenau: Botanische Jahrbucher fur Systematik, Pflanzengeschichte und Pflanzengeographie 12: 268. (1890) | (Coville) Wiegand: Bulletin of the Torrey Botanical Club 27: 521. (1900) |
Web links |
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