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three-flower rush, three-hulled rush

sharpflower rush

Habit Herbs, perennial, cespitose, 0.3–3.5 dm. Herbs, perennial, rhizomatous, to 8 dm.
Rhizomes

5–6 mm diam., nodes not swollen.

Culms

1–8, 0.3–0.5 mm diam.

erect, terete, 3 mm diam., smooth.

Cataphylls

1–2.

1, straw-colored, apex acute.

Leaves

basal, 2–4;

auricles slightly prolonged, rounded, scarious to ± leathery;

blade deeply channeled, 2–10 cm, mostly shorter than culms.

basal 1, cauline 2;

auricles 0.5 mm, apex rounded, cartilaginous;

blade 7–45 cm x 1–2 mm, terete, not scabrous.

Inflorescences

solitary heads, each with 2–3(–50) flowers;

primary bracts brownish, nearly equal to or slightly shorter thanabout equaling inflorescence.

terminal panicles of 70–120 heads, 6–10 cm, branches ascending;

primary bract erect;

heads 3–5(–8)-flowered, obconic, 2–4 mm diam.

Flowers

tepals pale brown or darker, oblong-lanceolate, 3–5 mm, outer and inner series nearly equal;

stamens 6, filaments 2.5–4 mm, anthers 0.6–1 mm;

styles 0.5–0.8 mm.

tepals dark reddish brown, lanceolate, apex acuminate to subulate tipte;

outer tepals 1.9–2.2 mm;

inner tepals 2–2.3 mm;

stamens 6, anthers 2 times filament length.

Capsules

tan, pseudo-3-locular, 3-gonous–cylindric, apex obtuse, mucronate.

inserted with beak exserted, straw-colored, 1-locular, narrowly ovoid, 2.3–2.4 mm, tapering to subulate tip, valves separating at dehiscence.

Seeds

tan or darker, fusiform, body 0.5–1 mm, tails 0.6–1 mm.

narrowly ovoid, 0.5–0.6 mm, not tailed;

body clear yellow-brown.

Juncus triglumis

Juncus acutiflorus

Phenology Fruiting fall.
Habitat Wet woods
Elevation 0–10 m (0–0 ft)
Distribution
from FNA
AK; CO; ID; MT; NM; OR; UT; WY; AB; BC; MB; NT; NU; ON; QC; SK; YT; Eurasia
[WildflowerSearch map]
[BONAP county map]
from FNA
NF; SPM; Europe; Asia; Africa
[BONAP county map]
Discussion

Varieties 3 (2 in the flora).

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

Key
1. Most proximal bracts of inflorescence obtuse to mucronate, usually much shorter than inflorescence; capsules well exserted from perianth, 4.5–7 mm, apex conic or rounded proximal to persistent style
var. triglumis
1. Most proximal bracts of infloresecence equal to or longer than inflorescence, apex long acuminate or awned; capsules included or barely exserted from perianth, 3–5 mm, apex nearly truncate proximal to persistent style
var. albescens
Source FNA vol. 22. FNA vol. 22.
Parent taxa Juncaceae > Juncus > subg. Alpini 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. 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. 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. trigonocarpus, J. uncialis, J. validus, J. vaseyi, J. xiphioides
J. acuminatus, 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. 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
Subordinate taxa
J. triglumis var. albescens, J. triglumis var. triglumis
Name authority Linnaeus: Sp. Pl. 1: 328. (1753) Ehrhart: in G. F. Hoffmann, Deutschl. Fl. 1: 125. (1791)
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