OregonFlora: Juncus effusus vs. Juncus inflexus

	Juncus effusus	Juncus inflexus
	pasture rush, soft rush	European blue rush
Habit	Plants perennial, 50–150 cm tall, cespitose; fruiting stems stout, usually 2–4.9 mm diameter above distal sheath; fresh upper stems shiny, smooth, dried stems with (12)18–26(32) weak low ridges, slender and relatively inconspicuous, visible on one side when dried, dried ridges capped with low dull cells (at 10×).
Leaves	lacking blades; distal sheaths dull or shiny; smooth or papillose; apex symmetrical or asymmetrical; thin or thickened, winged or not.
Inflorescences	dense or open; inflorescence bracts not swollen; erect in fruit.
Flowers	tepals 6, usually green to pale brown (dark brown-striped); stamens 3; filaments 0.4–0.7 mm; anthers 0.4–0.7 mm; styles 0–0.4 mm.
Capsules	1.6–2.5 mm; shorter than the tepals; light to dark brown; apices obtuse to acute (notched), 1-chambered.
Seeds	0.4–0.5 × 0.2 mm, reticulate, apiculate.

	Juncus effusus	Juncus inflexus
Distribution	[WildflowerSearch map] [BONAP county map]	[BONAP county map]
Discussion	The various subspecies include two introductions that often grow mingled with our native plants; the species can dominate wet pastures with heavy grazing. 9 subspecies; 3 subspecies in Oregon.	[Species with one variety or subspecies in Oregon.]
Source	Flora of Oregon, volume 1, page 276 Peter Zika	Flora of Oregon, volume 1
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. 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	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. 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
Subordinate taxa	J. effusus ssp. effusus, J. effusus ssp. pacificus, J. effusus ssp. solutus	J. inflexus ssp. inflexus
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	Local floras: OR, WA Local Web sites: 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 inflexus

pasture rush, soft rush

European blue rush

Habit

Plants perennial, 50–150 cm tall, cespitose; fruiting stems stout, usually 2–4.9 mm diameter above distal sheath; fresh upper stems shiny, smooth, dried stems with (12)18–26(32) weak low ridges, slender and relatively inconspicuous, visible on one side when dried, dried ridges capped with low dull cells (at 10×).

Leaves

lacking blades;

distal sheaths dull or shiny; smooth or papillose;

apex symmetrical or asymmetrical; thin or thickened, winged or not.

Inflorescences

dense or open;

inflorescence bracts not swollen; erect in fruit.

Flowers

tepals 6, usually green to pale brown (dark brown-striped);

stamens 3;

filaments 0.4–0.7 mm;

anthers 0.4–0.7 mm;

styles 0–0.4 mm.

Capsules

1.6–2.5 mm; shorter than the tepals; light to dark brown;

apices obtuse to acute (notched), 1-chambered.

Seeds

0.4–0.5 × 0.2 mm, reticulate, apiculate.

Juncus effusus

Juncus inflexus

Distribution

[WildflowerSearch map]

[BONAP county map]

Discussion

The various subspecies include two introductions that often grow mingled with our native plants; the species can dominate wet pastures with heavy grazing. 9 subspecies; 3 subspecies in Oregon.

[Species with one variety or subspecies in Oregon.]

Source

Flora of Oregon, volume 1, page 276
Peter Zika

Flora of Oregon, volume 1

Sibling taxa