Juncus articulatus |
Juncus kelloggii |
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joint-leaf rush, jointed rush |
Kellogg's dwarf rush, Kellogg's rush |
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Habit | Herbs, perennial, rhizomatous to nearly cespitose, 0.5–6(–10) dm. | Herbs, annual, cespitose, 0.1–0.55(–0.65) dm. |
Rhizomes | 2–3 mm diam., not swollen. |
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Culms | erect to decumbent (and floating), terete, 1–3 mm diam., smooth. |
to 100. |
Cataphylls | 1, maroon to straw-colored, apex acute to obtuse. |
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Leaves | basal 0–2, cauline (1–)3–6; auricles 0.5–1 mm, apex rounded, scarious; blade green to straw-colored, terete, 3.5–12 cm × 0.5–1.1 mm. |
to 2.5 cm × 0.1–0.3 mm. |
Inflorescences | terminal panicles of 3–30(–50) heads, 3.5–8 cm, branches spreading; primary bract erect; heads 3–10-flowered, obpyramidal to hemispheric, 6–8 mm diam. |
terminal clusters, each with 1–4 flowers; bracts subtending inflorescence 2–5, ovate to lanceolate, inconspicuous, 1–2.5 mm, membranous, apex acute to obtuse. |
Flowers | tepals green to straw-colored or dark brown, ovate to lanceolate, 1.8–3 mm; outer tepals with apex acute or acuminate; inner tepals with apex acute acuminate to obtuse; stamens 6, anthers equal to filament length. |
3-merous; : tepals dark reddish brown, 2–3.2 × 0.4–1 mm, margins unpigmented; inner series nearly equal to or slightly shorter than outer series, acute to acuminate; stamens 3, filaments 0.7–1.3 mm, anthers 0.3–0.5 mm; style 0.2–0.5 mm, stigma 0.4–1.3 mm. |
Capsules | exserted ca. 1 mm beyond perianth, chestnut brown to dark brown, imperfectly 3-locular, ellipsoid or ovoid, 2.8–4 mm, apex acute proximal to beak, valves separating at dehiscence. |
dark reddish, 3-locular, obovoid to ellipsoid, nearly equal to tepals, 1.8–2.9 × 1.2–1.6 mm. |
Seeds | obovoid, 0.5 mm, not tailed. |
ovoid, 0.4–0.55 mm, apiculate. |
n | = 17. |
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2n | = 80. |
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Juncus articulatus |
Juncus kelloggii |
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Phenology | Fruiting mid summer–fall. | Flowering and fruiting spring–early summer. |
Habitat | Wet ground in ditches, lake and stream margins, and a variety of other habitats, often a calciphile | Sandy and clayey damp soils around vernal pools, seepage areas, and low spots in fields and meadows |
Elevation | 0–3000 m (0–9800 ft) | 0–800 m (0–2600 ft) |
Distribution |
AK; AZ; CA; CO; CT; ID; IN; KY; MA; ME; MI; MN; NC; NE; NH; NJ; NM; NV; NY; OH; OR; PA; RI; SD; UT; VA; VT; WA; WV; BC; NB; NF; NS; ON; PE; QC; SPM; Eurasia
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CA; NV; OR; WA; BC
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Discussion | Juncus articulatus hybridizes with J. brevicaudatus (= J. ×fulvescens Fernald), J. alpinus (= J. ×alpiniformis Fernald), J. nodosus, and J. canadensis. Juncus articulatus var. obtusatus Engelmann appears to be intermediate with J. alpinus. It has spreading inflorescence branches but obtuse inner tepals. This may represent a backcross with J. alpinus. Recent evidence suggests that J. alpinus is a polyploid species with J. articulatus as one of its parents. (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. Graminifolii |
Sibling taxa | ||
Synonyms | J. articulatus var. obtusatus, J. articulatus var. stolonifer, J. lampocarpus | J. triformis var. brachystylus |
Name authority | Linnaeus: Sp. Pl. 1: 327. (1753) | Engelmann |
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