Juncus canadensis |
Juncus oxymeris |
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Canada rush, Canadian rush |
point rush |
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Habit | Herbs, perennial, cespitose, 3–10 dm. | Herbs, perennial, rhizomatous, 3–6 dm. |
Rhizomes | 1–2 mm diam. |
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Culms | erect, 1–5 mm diam., smooth. |
erect, 2–4 mm diam. |
Cataphylls | 0 or 1–2, straw-colored, apex rounded. |
0–1, straw-colored, apex narrowly acute. |
Leaves | basal 1, cauline 2–3; auricles 1–1.2 mm, apex rounded, scarious; blade terete, 7–22 cm × 1.2–3 mm. |
basal 1–3, cauline 3–4, straw-colored; auricles absent; blade 3–20 cm × 3–7 mm. |
Inflorescences | panicles or racemes of 3–50 heads, 2–20 cm, branches erect to ascending; primary bract erect; heads 5–50-flowered, obconic to spheric, 3–10 mm diam. |
panicles of 10–50 heads, 6–20 cm, erect to ascending branches; primary bract erect; heads 3–11-flowered, turbinate to hemispheric, 4–8 mm diam. |
Flowers | tepals green or straw-colored to reddish brown, lanceolate; outer tepals 2.7–3.8 mm, apex acuminate; inner tepals 2.9–4 mm, apex acuminate; stamens 3(–6), anthers 1/2 filament length. |
tepals straw-colored, lanceolate, 2.5–3.2 mm, nearly equal, apex acute to narrowly acuminate, mucronate; stamens 6, anthers 0.5–1.5 times length of filaments. |
Capsules | equaling perianth or exserted, chestnut brown, imperfectly 3-locular, lanceoloid, 3.3–4.5 mm, acute proximal to beak, valves separating at dehiscence. |
exserted, chestnut brown, 1-locular, broadly lanceoloid to narrowly oblong, 3.3–4.7 mm, apex tapering to beak, separating at dehiscence. |
Seeds | fusiform, 1.1–1.9 mm, tailed; body covered with whitish translucent veil. |
obovoid, 0.5 mm, not tailed. |
2n | = 80. |
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Juncus canadensis |
Juncus oxymeris |
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Phenology | Fruiting mid summer–fall. | Fruiting late spring–fall. |
Habitat | Salt, brackish, and calcareous marshes, acid bogs, roadsides, tidal flats, swamps, patterned fen, lake shores, beaches | Stream and lake shores, montane meadows and seasonally emergent wetlands |
Elevation | 0–200 m (0–700 ft) | 100–2000 m (300–6600 ft) |
Distribution |
AL; AR; CT; DC; DE; FL; GA; IA; IL; IN; KY; LA; MA; MD; ME; MI; MN; MO; MS; NC; NE; NH; NJ; NY; OH; OR; PA; RI; SC; SD; TN; VA; VT; WI; WV; MB; NB; NF; NS; ON; PE; QC; SPM
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CA; OR; WA; BC
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Discussion | Two varieties and two forms occurring within the flora have been recognized (M. L. Fernald 1945b). Juncus canadensis var. sparsiflorus has stiffly erect inflorescence branches, and the flowers are generally longer than those of var. canadensis. These varieties simply serve to give name to parts of the broad morphologic range of variation encountered in J. canadensis and do not appear to represent any distinct biological entities. Juncus canadensis and the following three species form a distinctive group: they have ve been variously treated as speecies (as here), varieties of J. canadensis, or as two species, J. canadensis and a polymorphic species, J. brachysephalus, encompassing the other three species (B. Boivin 1967–1979, part IV). Most of the species are easily recognized at their extremes but show a fair amount of overlap. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Juncus oxymeris should be expected in Mexico (Baja California). (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 22. | FNA vol. 22. |
Parent taxa | ||
Sibling taxa | ||
Synonyms | J. canadensis var. longicaudatus, J. canadensis var. sparsiflorus, J. longicaudatus, J. polycephalus var. paradoxus | J. acutiflorus |
Name authority | J. Gay ex Laharpe: in J. J. C. de Laharpe, Essai Monogr. Jonc. 46. (1825) | Engelmann |
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