Juncus tenuis |
Juncus nevadensis |
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path rush, poverty or slender rush, poverty rush, slender rush |
Nevada rush, Sierra rush |
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Habit | Herbs, perennial, tufted, 1.5–5 dm. | Herbs, perennial, rhizomatous, 0.5–7 dm. |
Rhizomes | densely branching. |
1 mm diam., not swollen. |
Culms | few–20. |
erect, terete, 1.5–3 mm diam., smooth. |
Cataphylls | 0–1, maroon or straw-colored, apex acute. |
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Leaves | basal, (1–)2–3; auricles 2–5 mm, apex acute, membranous; blade flat, 3–12 cm × 0.5–1 mm, margins entire. |
basal 1–3, cauline 1–2; auricles 1–3.2 mm, apex rounded to acute, membranaceous; blade green, laterally flattened, 1.5–31 cm × 0.5–2.2 mm. |
Inflorescences | 5–40-flowered, borne congested or branch internodes ca. as long as tepals, ssomewhat loose, 1–5 cm; primary bract usually longer than inflorescence. |
terminal panicles of 2–11 heads, 2–18 cm, branches erect to spreading; primary bract erect; heads 3–11-flowered, hemispheric to obpyramidal (rarely nearly spheric), 5–14 mm diam. |
Flowers | bracteoles 2; tepals greenish, lanceolate, 3.3–4.4 mm; outer and inner series nearly equal; stamens 6, filaments 0.5–0.9 mm, anthers 0.1–0.2 mm; style 0.1–0.2 mm. |
tepals dark brown to white, lanceolate, apex acute to acuminate, mucro subulate; outer tepals 2.8–6.2 mm; inner tepals 2.4–6 mm; stamens 6, anthers 1–2 times filament length. |
Capsules | tan or light brown, 1-locular to pseudo-3-locular, ellipsoid, (3.3–)3.8–4.7 × (1.1–)1.3–1.7 mm, nearly equal to tepals. |
included to slightly exserted, chestnut brown, ellipsoid, 2.3–3.7 mm, abruptly contracted to apex, apex acute proximal to beak, valves separating at dehiscence. |
Seeds | tan, ellipsoid to lunate, (0.52–)5.5–0.65(–0.7) mm, not tailed. |
ellipsoid, 0.4–0.5 mm, not tailed. |
2n | = 80. |
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Juncus tenuis |
Juncus nevadensis |
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Phenology | Flowering spring–early summer. | Fruiting early summer–fall. |
Habitat | Exposed or shaded sites in soils ranging from sandy to clayey under moist or drier conditions, oftentimes these sites naturally or otherwise disturbed (e.g., game or human trails) | Wet banks along margins of streams and lakes, marshes, bogs, sloughs, and wet or boggy prairies |
Elevation | 0–2600 m (0–8500 ft) | |
Distribution |
AK; AL; AR; AZ; CA; CO; CT; DC; DE; FL; GA; IA; ID; IL; IN; KS; KY; LA; MA; MD; ME; MI; MN; MO; MS; MT; NC; ND; NE; NH; NJ; NM; NV; NY; OH; OK; OR; PA; RI; SC; SD; TN; TX; UT; VA; VT; WA; WI; WV; WY; AB; BC; MB; NB; NS; ON; PE; QC; SK [Introduced worldwide]
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AZ; CA; CO; ID; MT; NM; NV; OR; UT; WA; WY; AB; SK
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Discussion | Juncus tenuis occurs throughout North America. It is particularly abundant in northeastern United States and eastern Canada, although infrequent in the south and west. Through the use of isozyme electrophoresis, hybridization can be demonstrated between various members of the Juncus tenuis complex, including Juncus tenuis, J. anthelatus, J. interior, J. secundus, and J. dichotomus (R. E. Brooks, unpubl.). Juncus ××oronensis is thought to be a hybrid between J. tenuis and J. vaseyi in the northeast. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
This variable species has been divided into five separate taxa in the past (F. J. Hermann 1964; C. L. Hitchcock et al. 1955–1969, vol. 1), but more recently, most of the variants have not been separated (A. Cronquist et al. 1972+, vol. 6). The Oregon coastal endemic, Juncus nevadensis var. inventus L. F. Henderson) C. L. Hitchcock, is at one extreme of the variation, having only a single head, fairly dark brown tepals 3.5–4.5 mm, anthers only slightly longer than the filaments, and a distinct habitat. The J. mertensianus var. columbianus segregate, however, approaches var. inventus in number of heads, and the other characters are so highly variable in the complex, they cannot be used alone to separate this variety. Therefore, we are not recognizing any infraspecific taxa at this time. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 22. | FNA vol. 22. |
Parent taxa | Juncaceae > Juncus > subg. Poiophylli | Juncaceae > Juncus > subg. Septati |
Sibling taxa | ||
Synonyms | J. bicornis, J. bicornis var. williamsii, J. macer, J. macer, J. macer var. williamsii, J. tenuis var. bicornis, J. tenuis var. multicornis, J. tenuis var. williamsii | J. badius, J. columbianus, J. mertensianuss subsp. gracilis, J. mertensianus var. badius, J. mertensianus var. columbianus, J. mertensianus var. gracilis, J. mertensianus var. suksdorfii, J. nevadensis var. badius, J. nevadensis var. columbianus, J. nevadensis var. inventus, J. phaeocephalus var. gracilis, J. suksdorfii, J. truncatus |
Name authority | Willdenow: Sp. Pl. 2(1): 214. (1799) | S. Watson: Proceedings of the American Academy of Arts and Sciences 14: 303. (1879) |
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