Juncus brevicaudatus

(Engelmann) Fernald

Rhodora 6: 35. 1904.

Common names: Narrow-panicled rush
IllustratedEndemic
Basionym: Juncus canadensis var. brevicaudatus Engelmann Trans. Acad. Sci. St. Louis 2: 436. 1866
Synonyms: Juncus canadensis var. coarctatus Engelmann Juncus canadensis var. kuntzei Buchenau Juncus coarctatus Rydberg Juncus kuntzei Juncus tweedyi
Treatment appears in FNA Volume 22.

Herbs, perennial, cespitose, 1.4–5.5 (–7) dm. Culms erect, terete, 1–3 mm diam., smooth. Cataphylls 0–1, straw-colored to pink, apex acute. Leaves: basal 1–3, cauline 1–2; auricles 0.5–3 mm, apex rounded to truncate, scarious; blade terete, 1.5–25 cm × 0.5–2.5 mm. Inflorescences terminal panicles or racemes of 2–35 heads, 1–12 cm, branches erect; primary bract erect; heads 2–8-flowered, ellipsoid to narrowly obconic, 2–9 mm diam. Flowers: tepals green to light-brown, lanceolate; outer tepals 2.3–3.1 mm, apex acuminate to rarely obtuse; inner tepals 2.5–3.2 mm, apex acuminate; stamens 3 (or 6), anthers 1/4–1/2 filament length. Capsules exserted, chestnut-brown, imperfectly 3-locular, narrowly ellipsoid to prismatic, 3.2–4.8 mm, apex acute proximal to beak, valves separating at dehiscence. Seeds fusiform, 0.7–1.2 mm, tailed; body covered with whitish translucent veil. 2n = 80.


Phenology: Fruiting mid summer–fall.
Habitat: Generally in acidic or peaty moist sites, including emergent shorelines and aroundg hot springs
Elevation: 100–2500 m

Distribution

V22 274-distribution-map.jpg

Alta., B.C., Man., N.B., Nfld. and Labr., N.S., Ont., P.E.I., Que., Sask., Ariz., Colo., Conn., Maine, Md., Mass., Mich., Minn., Mont., N.H., N.Y., N.C., Oreg., Pa., R.I., Tenn., Utah, Vt., Va., W.Va., Wis., Wyo.

Discussion

Populations from about around hot springs in the west have been separated as Juncus tweedyi Rydberg, but no morphologic distinction appears to exist between J. tweedyi and J. brevicaudatus.

Selected References

None.

Lower Taxa

None.

"dm" is not declared as a valid unit of measurement for this property.

... more about "Juncus brevicaudatus"
persistent +
acute +, acuminate +  and rarely obtuse +
scarious +
0.05 cm0.5 mm <br />5.0e-4 m <br /> (0.3 cm3 mm <br />0.003 m <br />) +
Ralph E. Brooks* +  and Steven E. Clemants* +
(Engelmann) Fernald +
Juncus canadensis var. brevicaudatus +
1.5 cm15 mm <br />0.015 m <br /> (25 cm250 mm <br />0.25 m <br />) +
0.05 cm0.5 mm <br />5.0e-4 m <br /> (0.25 cm2.5 mm <br />0.0025 m <br />) +
ascending +  and erect +
terete +, involute +  and flat +
chestnut-brown +
narrowly ellipsoid;prismatic +
0.32 cm3.2 mm <br />0.0032 m <br /> (0.48 cm4.8 mm <br />0.0048 m <br />) +
straw-colored +  and pink +
Narrow-panicled rush +
Alta. +, B.C. +, Man. +, N.B. +, Nfld. and Labr. +, N.S. +, Ont. +, P.E.I. +, Que. +, Sask. +, Ariz. +, Colo. +, Conn. +, Maine +, Md. +, Mass. +, Mich. +, Minn. +, Mont. +, N.H. +, N.Y. +, N.C. +, Oreg. +, Pa. +, R.I. +, Tenn. +, Utah +, Vt. +, Va. +, W.Va. +, Wis. +  and Wyo. +
100–2500 m +
arranged +  and cluster +
headlike +
Generally in acidic or peaty moist sites, including emergent shorelines and aroundg hot springs +
2-8-flowered +
0.2 cm2 mm <br />0.002 m <br /> (0.9 cm9 mm <br />0.009 m <br />) +
ellipsoid +  and narrowly obconic +
pseudoaxillary +  and terminal +
1 cm10 mm <br />0.01 m <br /> (12 cm120 mm <br />0.12 m <br />) +
0.25 cm2.5 mm <br />0.0025 m <br /> (0.32 cm3.2 mm <br />0.0032 m <br />) +
cauline +  and basal +
3 +  and 1 +
0.23 cm2.3 mm <br />0.0023 m <br /> (0.31 cm3.1 mm <br />0.0031 m <br />) +
green;brown or purplish black +
persistent +
Fruiting mid summer–fall. +
parietal +  and axile +
tailed;fusiform +
0.07 cm0.7 mm <br />7.0e-4 m <br /> (0.12 cm1.2 mm <br />0.0012 m <br />) +
green;brown or purplish black +
persistent +
Illustrated +  and Endemic +
generally longer +
Juncus canadensis var. coarctatus +, Juncus canadensis var. kuntzei +, Juncus coarctatus +, Juncus kuntzei +  and Juncus tweedyi +
Juncus brevicaudatus +
Juncus subg. Septati +
species +
green +  and light-brown +
lanceolate +
1 cm10 mm <br />0.01 m <br /> (12 cm120 mm <br />0.12 m <br />) +
1 cm10 mm <br />0.01 m <br /> (12 cm120 mm <br />0.12 m <br />) +
whitish translucent +
herb +  and cespitose +