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weak rush

blunt-flower rush

Habit Herbs, perennial, cespitose, 1–2.5 dm. Herbs, perennial, rhizomatous, 7–10 dm.
Rhizomes

3–7 mm diam., nodes not swollen.

Culms

erect, terete, 1–2 mm diam., smooth.

erect, terete, 2–4 mm diam.

Cataphylls

0–1, maroon or dark green, apex acute.

2–3, straw-colored, apex rounded.

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.

basal 0, cauline 1;

auricles 0.5–1.5 mm, apex blunt, cartilaginous;

blade 25–35 cm × 1–2 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.

terminal panicles of 24–60 heads, 5–10 cm, branches spreading;

primary bract erect;

heads 15–50-flowered, spheric, 4.5–6 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.

tepals light brown, lanceolate to oblong, 2–2.5 mm, nearly equal;

stamens 6, anthers longer than filament.

Capsules

exserted, straw-colored, 1-locular, narrowly ellipsoid to lanceoloid, 2.8–3.7 7(–4.2) mm, apex acute, valves separating at dehiscence.

included with beak slightly exserted, chestnut brown, 3-locular, ovoid, 2.5 mm, apex acute proximal to beak, valves separating at dehiscence, fertile throughout or only proximal to middle.

Seeds

ellipsoid, 0.3–0.4 mm, not tailed;

body clear yellow-brown.

not seen.

Juncus debilis

Juncus pervetus

Phenology Fruiting summer. Fruiting fall.
Habitat Marshy shores, in small streams, swamps, wet clearings, spring runs, commonly in very soft mucky substrates Upper border of salt marsh
Elevation 0–700 m (0–2300 ft) 0 m (0 ft)
Distribution
from FNA
AL; AR; DE; FL; GA; IL; KY; LA; MD; MO; MS; NC; NJ; NY; PA; SC; TN; TX; VA; Mexicos (Chiapas); Central America (Honduras)
[WildflowerSearch map]
[BONAP county map]
from FNA
MA
Discussion

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

(Discussion copyrighted by Flora of North America; reprinted with permission.)

All sheets that I have seen have aborted seeds. Juncus pervetus was thought to be Juncus subnodulosus, a European native (H. Weimarck 1946). It has been shown that this is a distinct species, however (S. Snogerup and B. Snogerup 1996). It would appear that this species is now extinct.

(Discussion copyrighted by Flora of North America; reprinted with permission.)

Source FNA vol. 22. FNA vol. 22.
Parent taxa Juncaceae > Juncus > subg. Septati Juncaceae > Juncus > subg. Septati
Sibling taxa
J. acuminatus, J. acutiflorus, J. acutus, J. alpinoarticulatus, J. anthelatus, J. arcticus, J. articulatus, J. biglumis, J. bolanderi, J. brachycarpus, J. brachycephalus, J. brachyphyllus, J. brevicaudatus, J. bryoides, J. bufonius, J. bulbosus, J. caesariensis, J. canadensis, J. capillaris, J. capitatus, J. castaneus, J. chlorocephalus, J. compressus, J. confusus, J. cooperi, J. coriaceus, J. covillei, J. dichotomus, J. diffusissimus, J. drummondii, J. dubius, J. dudleyi, J. effusus, J. elliottii, J. ensifolius, J. falcatus, J. filiformis, J. filipendulus, J. georgianus, J. gerardii, J. greenei, J. gymnocarpus, J. hallii, J. hemiendytus, J. howellii, J. inflexus, J. interior, J. kelloggii, J. leiospermus, J. lesueurii, J. longistylis, J. luciensis, J. macrandrus, J. macrophyllus, J. marginatus, J. maritimus, J. megacephalus, J. mertensianus, J. militaris, J. nevadensis, J. nodatus, J. nodosus, J. occidentalis, J. orthophyllus, J. oxymeris, J. parryi, J. patens, J. pelocarpus, J. pervetus, J. phaeocephalus, J. polycephalus, J. regelii, J. repens, J. roemerianus, J. scirpoides, J. secundus, J. squarrosus, J. stygius, J. subcaudatus, J. subtilis, J. supiniformis, J. tenuis, J. texanus, J. textilis, J. tiehmii, J. torreyi, J. trifidus, J. triformis, J. triglumis, J. trigonocarpus, J. uncialis, J. validus, J. vaseyi, J. xiphioides
J. acuminatus, J. acutiflorus, J. acutus, J. alpinoarticulatus, J. anthelatus, J. arcticus, J. articulatus, J. biglumis, J. bolanderi, J. brachycarpus, J. brachycephalus, J. brachyphyllus, J. brevicaudatus, J. bryoides, J. bufonius, J. bulbosus, J. caesariensis, J. canadensis, J. capillaris, J. capitatus, J. castaneus, J. chlorocephalus, J. compressus, J. confusus, J. cooperi, J. coriaceus, J. covillei, J. debilis, J. dichotomus, J. diffusissimus, J. drummondii, J. dubius, J. dudleyi, J. effusus, J. elliottii, J. ensifolius, J. falcatus, J. filiformis, J. filipendulus, J. georgianus, J. gerardii, J. greenei, J. gymnocarpus, J. hallii, J. hemiendytus, J. howellii, J. inflexus, J. interior, J. kelloggii, J. leiospermus, J. lesueurii, J. longistylis, J. luciensis, J. macrandrus, J. macrophyllus, J. marginatus, J. maritimus, J. megacephalus, J. mertensianus, J. militaris, J. nevadensis, J. nodatus, J. nodosus, J. occidentalis, J. orthophyllus, J. oxymeris, J. parryi, J. patens, J. pelocarpus, J. phaeocephalus, J. polycephalus, J. regelii, J. repens, J. roemerianus, J. scirpoides, J. secundus, J. squarrosus, J. stygius, J. subcaudatus, J. subtilis, J. supiniformis, J. tenuis, J. texanus, J. textilis, J. tiehmii, J. torreyi, J. trifidus, J. triformis, J. triglumis, J. trigonocarpus, J. uncialis, J. validus, J. vaseyi, J. xiphioides
Synonyms J. acuminatus var. debilis, J. radicans
Name authority A. Gray: Manual 481506. (1848) Fernald: Rhodora 19: 17. (1917)
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