Flora of North America species comparison

The green links below add additional plants to the comparison table. Blue links lead to other Web sites.
enable glossary links

Juncus effusus

Juncus occidentalis

common bog rush, common rush, common soft rush, pasture rush, soft or lamp rush, soft rush

prairie rush, slender juncus, western rush
Habit Herbs, perennial, 4–13 dm. Herbs, perennial, cespitose, 3–6 dm.
Rhizomes

short -branched, forming distinct, often large clumps.

densely branching.
Culms

erect, terete, 1–2.5 mm diam. at top of sheaths.

few–20.
Cataphylls

several.

Leaves

blade absent.

basal, (1–)2–3;

auricles 0.5–1(–1.5) mm, apex acutish, membranous;

blade flat, 5–15 cm × 0.5–1.3 mm, margins entire.
Inflorescences

lateral, compound dichasia, many flowered;

primary bract erect, terete, extending well beyond dichasium.

5–50-flowered, somewhat loose, 1–7 cm;

primary bract usually longer than inflorescence.
Flowers

tepals tan or darker, usually with greenish midstripe, lanceolate, 1.9–3.5 mm;

inner slightly shorter;

stamens 3, filaments 0.5–0.8 mm, anthers 0.5–0.8 mm;

style 0.2 mm.

bracteoles 2;

tepals greenish, lanceolate, (3.5–)5 mm;

outer and inner series nearly equal;

stamens 6, filaments 0.5–1 mm, anthers 0.1–0.3 mm;

style 0.1–0.2 mm.
Capsules

greenish tan or darker, 3-locular, broadly ellipsoid to oblate, 1.5–3.2 mm.

light brown, 1-locular to pseudo-3-locular, ellipsoid, (3–)5–4.5 × 1.2–1.8 mm, nearly equal to shorter than tepals.
Seeds

amber, (0.3–)0.4–0.5 mm.

tan, ellipsoid to lunate, 5.5–0.7 mm, not tailed.
2n

= 40, 42.

= 80.

Juncus effusus

Juncus occidentalis
Phenology Flowering summer, fruiting summer–fall. Flowering spring–early summer.
Habitat Swamps and their edges, marshes, moist meadows, and moist or saturated soils, often conspicuous in pasture meadows where it is shunned by grazing animals Moist, usually exposed sites in clayey or sandy soil around springs, along rivers and streams, and around lakes
Elevation Habitat??; 0–2500 m [Habitat??; 0–8200 ft] below 2300 m [below 7500 ft]
Distribution
map from FNA
AK; AL; AR; AZ; CA; CO; CT; DC; DE; FL; GA; IA; ID; IL; IN; KS; KY; LA; MA; MD; ME; MI; MN; MO; MS; MT; NC; NE; NH; NJ; NV; NY; OH; OK; OR; PA; RI; SC; TN; TX; VA; VT; WA; WI; WV; WV; BC; MB; NB; NF; NS; ON; PE; QC
[WildflowerSearch map]
[BONAP county map]
map from FNA
AZ; CA; ID; NV; OR; WA
[WildflowerSearch map]
[BONAP county map]
Discussion

The Juncus effusus complex has been variously recognized as containing several species or a single species with numerous infraspecific taxa. Unfortunately, North American treatments have dealt primarily with taxa in either the eastern or western portions of the continent. In considering the continent as a whole, little sense can be made of these treatments. The North American J. effusus complex is one that is in obvious need of modern systematic scrutiny.

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

Juncus occidentalis should perhaps be considered a robust variant of J. tenuis.

(Discussion copyrighted by Flora of North America; reprinted with permission.)
Parent taxa Juncaceae > Juncus > subg. Genuini Juncaceae > Juncus > subg. Poiophylli
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. 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. 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
Synonyms J. conglomeratus, J. effusus var. brunneus, J. effusus var. caeruleomontanus, J. effusus var. costulatus, J. effusus var. dicipiens, J. effusus var. exiguus, J. effusus var. gracilis, J. effusus var. pylaei, J. effusus var. solutus, J. effusus var. subglomeratus, J. griscomii J. tenuis var. occidentalis, J. tenuis var. congestus
Name authority Linnaeus: Sp. Pl. 1: 326. (1753) (Coville) Wiegand: Bulletin of the Torrey Botanical Club 27: 521. (1900)
Source FNA vol. 22. Treatment authors: Ralph E. Brooks*, Steven E. Clemants*. FNA vol. 22. Treatment authors: Ralph E. Brooks*, Steven E. Clemants*.
Web links 
Unless otherwise noted, all data comes from the online version of the Flora of North America, who have made most of their content available via a Creative Commons license (CC BY 4.0).



Type/paste one or more Latin names into the boxes above; matching taxa will show up below the box as you type. You can use the up/down arrow keys to move through the list.

(If the plant you're looking for doesn't show up in the auto-complete list, that means it either isn't described in Flora of North America yet, or it's listed under a synonym. And please note that Flora of North America is still missing several plant families, including Boraginaceae and Polemoniaceae.)

The species comparison tool is brought to you by:
Northwest Wildflowers