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 acutus

Juncus castaneus

sharp rush, spiny rush

chestnut rush
Habit Herbs, perennial, strongly rhizomatous, 1–4 dm.
Culms

solitary, 1–2 mm diam.
Cataphylls

1–2.
Leaves

partially cauline, 3–5, auricles absent distally, rounded proximally;

blade channeled, to 20 cm, reduced distally.
Inflorescences

glomerules, 1–3(–5), each with 2–10 flowers;

peduncles 0.4–1.5 cm;

primary bracts somewhat inflated, usually surpassing inflorescence.
Flowers

bracteoles absent;

tepals brown or occasionally paler, lanceolate, 4.5–6.6 mm, apex acute to obtuse;

inner series slightly shorter;

stamens 6, filaments 2.5–3.5 mm, anthers 0.6–1.3 mm;

style 1–1.3 mm.
Capsules

chestnut brown, 3-locular, narrowly oblong, 6.5–8.5 × 1.8–2.3 mm.
Seeds

pale yellow, fusiform, body 0.6–0.7 mm, tails 0.8–1.1 mm.
2n

= 60, 90, 120.

Juncus acutus

Juncus castaneus
Phenology Flowering and fruiting late spring–summer.
Habitat Tundra, subalpine and alpine bogs and meadows, and along streams in gravelly or clayey soils
Elevation 10–3700 m (0–12100 ft)
Distribution
from FNA
AZ; CA; NV; South America; Mexico (Baja Calif); South Africa; Atlantic Islands
[WildflowerSearch map]
[BONAP county map]
from FNA
AK; CO; MT; NM; NV; UT; WY; AB; BC; LB; MB; NT; NU; ON; QC; SK; YT; Greenland; Europe; Asia
[BONAP county map]
Discussion

Subspecies 2 (1 in the flora).

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

In southern Alaska some plants with several many-flowered heads and capsules about double the length of the perianth have been referred to the Asian Juncus castaneus subsp. leucochlamys. The distinction, however, seems dubious without further investigation.

(Discussion copyrighted by Flora of North America; reprinted with permission.)
Source FNA vol. 22, p. 237. FNA vol. 22.
Parent taxa Juncaceae > Juncus > subg. Juncus Juncaceae > Juncus > subg. Alpini
Sibling taxa
J. acuminatus, J. acutiflorus, 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
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. 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. acutus subsp. leopoldii
Synonyms J. castaneus var. pallidus, J. castaneus subsp. leucochlamys, J. leucochlamys
Name authority Linnaeus: Sp. Pl. 1: 325. (1753) Smith: Fl. Brit. 1: 383. (1800)
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 Fabaceae, Apiaceae, Boraginaceae, and Polemoniaceae.)

Choose a data source: Flora of North America

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