OregonFlora: Juncus tenuis

	Juncus tenuis
	path rush, poverty rush, slender rush
Habit	Plants perennial, 15–50 cm tall, cespitose, usually delicate, base usually green to brown, with 0–1(2) strong longitudinal stem ridges visible on a side.
Leaves	thin and wiry; blade flat and slightly inrolled, usually 1–8 mm on early season shoots; dirty white or translucent, scarious; acute or acuminate; auricles soft and thin.
Inflorescences	cymes, usually small, 1–6 cm; individual flowers often longer than internodes; bractlets subtending flowers usually acute (blunt).
Flowers	tepals 6, 3–4.1 mm, green to reddish; tips acuminate; stamens 6; filaments 0.6–1.2 mm; anthers usually 0.4–0.6(0.8)mm; styles 0.1–0.3(0.5)mm.
Capsules	usually 2.5–3 mm; more than 75% the length of; and shorter than the tepals, pale brown; apex usually blunt (acute), not crested, 1-chambered.
Seeds	0.4–0.5 × 0.2–0.25 mm, apiculate.
2n	=40, 80.

	Juncus tenuis
Distribution	[WildflowerSearch map] [BONAP county map]
Discussion	Shores, swales, springs, dune hollows, wet woods, marshes, damp paths, ditches, cranberry farms, moist disturbed sites. 0–1800m. BW, Casc, CR, Est, Lava, Sisk, WV. CA, NV, ID, WA; throughout most of North America. Native. Juncus tenuis is usually much smaller than Juncus anthelatus. The blunt unridged capsules separate J. tenuis from J. confusus, J. occidentalis, and J. trilocularis.
Source	Flora of Oregon, volume 1, page 284 Peter Zika
Sibling taxa	J. acuminatus, J. anthelatus, J. articulatus, J. balticus, J. bolanderi, J. brevicaudatus, J. breweri, J. bryoides, J. bufonius, J. bulbosus, J. canadensis, J. capillaris, J. capitatus, J. compressus, J. confusus, J. conglomeratus, J. covillei, J. diffusissimus, J. drummondii, J. dudleyi, J. effusus, J. ensifolius, J. ensifolius x Juncus nevadensis, J. exiguus, J. falcatus, J. filiformis, J. gerardi, J. hemiendytus, J. hesperius, J. howellii, J. inflexus, J. interior, J. kelloggii, J. laccatus, J. lescurii, J. longistylis, J. marginatus, J. mertensianus, J. mexicanus, J. nevadensis, J. occidentalis, J. orthophyllus, J. oxymeris, J. parryi, J. patens, J. pelocarpus, J. planifolius, J. ranarius, J. regelii, J. saximontanus, J. supiniformis, J. tiehmii, J. torreyi, J. triglumis, J. trilocularis, J. uncialis
Synonyms	Juncus tenuis var. tenuis
Web links	Local floras: BC, CA, OR, WA Local Web sites: CalFlora, CalPhotos, Flora NW, PNW Herbaria WildflowerSearch iNaturalist (observations) USDA Plants Database LBJ Wildflower Center SEINet Plants of the World Online Encyclopedia of Life Wikipedia Google Image Search

Juncus tenuis

path rush, poverty rush, slender rush

Habit

Plants perennial, 15–50 cm tall, cespitose, usually delicate, base usually green to brown, with 0–1(2) strong longitudinal stem ridges visible on a side.

Leaves

thin and wiry;

blade flat and slightly inrolled, usually 1–8 mm on early season shoots; dirty white or translucent, scarious; acute or acuminate;

auricles soft and thin.

Inflorescences

cymes, usually small, 1–6 cm; individual flowers often longer than internodes;

bractlets subtending flowers usually acute (blunt).

Flowers

tepals 6, 3–4.1 mm, green to reddish;

tips acuminate;

stamens 6;

filaments 0.6–1.2 mm;

anthers usually 0.4–0.6(0.8)mm;

styles 0.1–0.3(0.5)mm.

Capsules

usually 2.5–3 mm; more than 75% the length of; and shorter than the tepals, pale brown;

apex usually blunt (acute), not crested, 1-chambered.

Seeds

0.4–0.5 × 0.2–0.25 mm, apiculate.

=40, 80.

Juncus tenuis

Distribution

[WildflowerSearch map]

[BONAP county map]

Discussion

Shores, swales, springs, dune hollows, wet woods, marshes, damp paths, ditches, cranberry farms, moist disturbed sites. 0–1800m. BW, Casc, CR, Est, Lava, Sisk, WV. CA, NV, ID, WA; throughout most of North America. Native.

Juncus tenuis is usually much smaller than Juncus anthelatus. The blunt unridged capsules separate J. tenuis from J. confusus, J. occidentalis, and J. trilocularis.

Source

Flora of Oregon, volume 1, page 284
Peter Zika

Sibling taxa

J. acuminatus, J. anthelatus, J. articulatus, J. balticus, J. bolanderi, J. brevicaudatus, J. breweri, J. bryoides, J. bufonius, J. bulbosus, J. canadensis, J. capillaris, J. capitatus, J. compressus, J. confusus, J. conglomeratus, J. covillei, J. diffusissimus, J. drummondii, J. dudleyi, J. effusus, J. ensifolius, J. ensifolius x Juncus nevadensis, J. exiguus, J. falcatus, J. filiformis, J. gerardi, J. hemiendytus, J. hesperius, J. howellii, J. inflexus, J. interior, J. kelloggii, J. laccatus, J. lescurii, J. longistylis, J. marginatus, J. mertensianus, J. mexicanus, J. nevadensis, J. occidentalis, J. orthophyllus, J. oxymeris, J. parryi, J. patens, J. pelocarpus, J. planifolius, J. ranarius, J. regelii, J. saximontanus, J. supiniformis, J. tiehmii, J. torreyi, J. triglumis, J. trilocularis, J. uncialis

Synonyms

Juncus tenuis var. tenuis

Web links

Local floras: BC, CA, OR, WA
Local Web sites: CalFlora, CalPhotos, Flora NW, PNW Herbaria
WildflowerSearch
iNaturalist (observations)
USDA Plants Database
LBJ Wildflower Center
SEINet
Plants of the World Online
Encyclopedia of Life
Wikipedia
Google Image Search

Unless otherwise noted, all data comes from OregonFlora.

Choose a data source: Flora of North America, OregonFlora, UW Burke Herbarium

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Juncus tenuis

Juncus tenuis