Juncus debilis

A. Gray

Manual 481506. 1848.

Common names: Weak rush
Synonyms: Juncus acuminatus var. debilis (A. Gray) Engelmann Juncus radicans Schlechtendal
Treatment appears in FNA Volume 22.

Herbs, perennial, cespitose, 1–2.5 dm. Culms erect, terete, 1–2 mm diam., smooth. Cataphylls 0–1, maroon or dark green, apex acute. Leaves: basal 0–1, cauline 1–3; auricles 1–1.5 mm, apex rounded, scarious; blade maroon or dark green, terete, 1–12.5 cm × 0.5–1.5 mm. Inflorescences terminal panicles of 3–50 heads, 2–8 cm, branches ascending to spreading; primary bract erect; heads 2–10-flowered, obpyramidal, 2–5 mm diam. Flowers: tepals green to straw-colored, lanceolate, 1.8–2.3 (–2.5) mm, apex sharply acuminate; stamens 3, 1/2 filament length. Capsules exserted, straw-colored, 1-locular, narrowly ellipsoid to lanceoloid, 2.8–3.7 7 (–4.2) mm, apex acute, valves separating at dehiscence. Seeds ellipsoid, 0.3–0.4 mm, not tailed; body clear yellowbrown.


Phenology: Fruiting summer.
Habitat: Marshy shores, in small streams, swamps, wet clearings, spring runs, commonly in very soft mucky substrates
Elevation: 0–700 m

Distribution

V22 196-distribution-map.jpg

Ala., Ark., Del., Fla., Ga., Ill., Ky., La., Md., Miss., Mo., N.J., N.Y., N.C., Pa., S.C., Tenn., Tex., Va., Mexicos (Chiapas), Central America (Honduras)

Discussion

Juncus debilis A. Gray is a name being proposed for conservation.

Selected References

None.

Lower Taxa

None.

"-7mm" is not declared as a valid unit of measurement for this property."-7mm" is not declared as a valid unit of measurement for this property.

... more about "Juncus debilis"
persistent +
acute +, acuminate +  and rounded +
scarious +
0.1 cm1 mm <br />0.001 m <br /> (0.15 cm1.5 mm <br />0.0015 m <br />) +
Ralph E. Brooks* +  and Steven E. Clemants* +
A. Gray +
dark green +  and maroon +
1 cm10 mm <br />0.01 m <br /> (12.5 cm125 mm <br />0.125 m <br />) +
0.05 cm0.5 mm <br />5.0e-4 m <br /> (0.15 cm1.5 mm <br />0.0015 m <br />) +
clear yellowbrown +
ascending +  and erect +
terete +, involute +  and flat +
ascending;spreading +
straw-colored +
narrowly ellipsoid;lanceoloid +
dark green +  and maroon +
Weak rush +
Ala. +, Ark. +, Del. +, Fla. +, Ga. +, Ill. +, Ky. +, La. +, Md. +, Miss. +, Mo. +, N.J. +, N.Y. +, N.C. +, Pa. +, S.C. +, Tenn. +, Tex. +, Va. +, Mexicos (Chiapas) +  and Central America (Honduras) +
0–700 m +
arranged +  and cluster +
headlike +
Marshy shores, in small streams, swamps, wet clearings, spring runs, commonly in very soft mucky substrates +
2-10-flowered +
0.2 cm2 mm <br />0.002 m <br /> (0.5 cm5 mm <br />0.005 m <br />) +
obpyramidal +
pseudoaxillary +  and terminal +
cauline +  and basal +
3 +  and 1 +
green;brown or purplish black +
persistent +
Fruiting summer. +
parietal +  and axile +
not tailed;ellipsoid +
0.03 cm0.3 mm <br />3.0e-4 m <br /> (0.04 cm0.4 mm <br />4.0e-4 m <br />) +
green;brown or purplish black +
persistent +
1/2 +  and 3 +
generally longer +
Juncus acuminatus var. debilis +  and Juncus radicans +
Juncus debilis +
Juncus subg. Septati +
species +
0.23 cm2.3 mm <br />0.0023 m <br /> (0.25 cm2.5 mm <br />0.0025 m <br />) +
green +  and straw-colored +
lanceolate +
0.18 cm1.8 mm <br />0.0018 m <br /> (0.23 cm2.3 mm <br />0.0023 m <br />) +
2 cm20 mm <br />0.02 m <br /> (8 cm80 mm <br />0.08 m <br />) +
herb +  and cespitose +