OregonFlora: Juncus bulbosus

	Juncus bulbosus
	bulbous rush, spreading rush
Habit	Plants perennial, sometimes flowering in the first year, 1–30 cm tall, cespitose, sometimes tuberous at nodes, stems sometimes prostrate, trailing, stoloniferous, rooting at nodes, upper nodes sometimes forming leafy bulblets.
Leaves	round; hollow or several-chambered, septate at least in part; auricles 1–2 mm.
Inflorescences	open; (2)6–16 clusters; clusters 2–12-flowered; flowers often forming leafy bulblets.
Flowers	tepals 6, 1.8–3.4 mm, green, red, or brown (dark brown); inner tepal margins flat; tips usually blunt, hooded; stamens (3)6; filaments 0.6–1 mm; longer than or equaling anthers; anthers 0.2–0.8 mm; styles 0.2–0.5 mm.
Capsules	usually 0.1–0.4 mm longer than or equaling tepals, brown to dark brown, abruptly tapered to apices; blunt or acute, 1-chambered.
Seeds	ellipsoid to ovoid, 0.4–0.6 × 0.2–0.25 mm, apiculate.
2n	=40.

	Juncus bulbosus
Distribution	[BONAP county map]
Discussion	Damp grassy disturbed ground, lakeshores. 0–50 m. Est. CA, WA; north to British Columbia, northeastern Canada and NY; Australia, Europe, Mauritius, New Zealand. Exotic. This species is uncommon but can invade natural wetland systems. The capsule is rounded at the tip, differing from the acute to acuminate capsules of J. supiniformis. Juncus supiniformis capsules are more than 1 mm longer than the tepals. Juncus articulatus is coarser and has capsules more exserted than J. bulbosus.
Source	Flora of Oregon, volume 1, page 273 Peter Zika
Sibling taxa	J. acuminatus, J. anthelatus, J. articulatus, J. balticus, J. bolanderi, J. brevicaudatus, J. breweri, J. bryoides, J. bufonius, 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. tenuis, J. tiehmii, J. torreyi, J. triglumis, J. trilocularis, J. uncialis
Synonyms	Juncus supinus
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 bulbosus

bulbous rush, spreading rush

Habit

Plants perennial, sometimes flowering in the first year, 1–30 cm tall, cespitose, sometimes tuberous at nodes, stems sometimes prostrate, trailing, stoloniferous, rooting at nodes, upper nodes sometimes forming leafy bulblets.

Leaves

round; hollow or several-chambered, septate at least in part;

auricles 1–2 mm.

Inflorescences

open; (2)6–16 clusters; clusters 2–12-flowered;

flowers often forming leafy bulblets.

Flowers

tepals 6, 1.8–3.4 mm, green, red, or brown (dark brown);

inner tepal margins flat;

tips usually blunt, hooded;

stamens (3)6;

filaments 0.6–1 mm; longer than or equaling anthers;

anthers 0.2–0.8 mm;

styles 0.2–0.5 mm.

Capsules

usually 0.1–0.4 mm longer than or equaling tepals, brown to dark brown, abruptly tapered to apices; blunt or acute, 1-chambered.

Seeds

ellipsoid to ovoid, 0.4–0.6 × 0.2–0.25 mm, apiculate.

=40.

Juncus bulbosus

Distribution

[BONAP county map]

Discussion

Damp grassy disturbed ground, lakeshores. 0–50 m. Est. CA, WA; north to British Columbia, northeastern Canada and NY; Australia, Europe, Mauritius, New Zealand. Exotic.

This species is uncommon but can invade natural wetland systems. The capsule is rounded at the tip, differing from the acute to acuminate capsules of J. supiniformis. Juncus supiniformis capsules are more than 1 mm longer than the tepals. Juncus articulatus is coarser and has capsules more exserted than J. bulbosus.

Source

Flora of Oregon, volume 1, page 273
Peter Zika

Sibling taxa

J. acuminatus, J. anthelatus, J. articulatus, J. balticus, J. bolanderi, J. brevicaudatus, J. breweri, J. bryoides, J. bufonius, 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. tenuis, J. tiehmii, J. torreyi, J. triglumis, J. trilocularis, J. uncialis

Synonyms

Juncus supinus

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 bulbosus

Juncus bulbosus