FNA: Juncus acutus vs. Juncus dudleyi

	Juncus acutus	Juncus dudleyi
	sharp rush, spiny rush	Dudley's rush
Habit		Herbs, perennial, 2–10 dm.
Rhizomes		densely branching.
Culms		1–20.
Cataphylls		1–3.
Leaves		basal, 2–3; auricles yellowish, 0.2–0.4 mm, leathery; blade flat, 5–30 cm × 0.5–1 mm, margins entire, turned up, occasionally involute.
Inflorescences		compact and few flowered to loose and lax with to 80 flowers, 1.5–5(–9) cm; primary bract usually exceeding inflorescence.
Flowers		bracteoles 2; tepals greenish, lanceolate, 4–5 mm; inner series nearly equal, spreading in fruit, nearly equal to or exceeding capsule; stamens 6, filaments 0.8–1.2 mm, anthers 0.6–1 mm; style 0.2 mm.
Capsules		tan, 1-locular to pseudo-3-locular, ellipsoid, 2.9–3.6 × 1.5–1.9 mm.
Seeds		tan to amber, ellipsoid to lunate, 0.4–0.67 mm, not tailed.
2n		= ca. 84.

	Juncus acutus	Juncus dudleyi
Phenology		Flowering and fruiting spring–early summer.
Habitat		Exposed or shaded sites in sandy to clayey soils, usually moist areas such as along stream banks, ditches, around springs
Distribution	AZ; CA; NV; South America; Mexico (Baja Calif); South Africa; Atlantic Islands [WildflowerSearch map] [BONAP county map]	AK; AR; AZ; CA; CO; CT; DC; DE; IA; ID; IL; IN; KS; KY; LA; MA; MD; ME; MI; MN; MO; MS; MT; ND; NE; NH; NJ; NM; NV; NY; OH; OK; OR; PA; RI; SD; TN; TX; UT; VA; VT; WA; WI; WV; WY; AB; BC; MB; NB; NL; NS; NT; ON; PE; QC; SK; YT; Mexico [WildflowerSearch map] [BONAP county map]
Discussion	Subspecies 2 (1 in the flora). (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. Poiophylli
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. castaneus, J. chlorocephalus, J. compressus, J. confusus, J. cooperi, J. coriaceus, J. covillei, J. debilis, J. dichotomus, J. diffusissimus, J. drummondii, J. dubius, 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. tenuis var. dudleyi, J. tenuis var. uniflorus
Name authority	Linnaeus: Sp. Pl. 1: 325. (1753)	Wiegand: Bulletin of the Torrey Botanical Club 27: 524. (1900)
Web links	Local Web sites: CalFlora, CalPhotos WildflowerSearch iNaturalist (observations) USDA Plants Database LBJ Wildflower Center SEINet Plants of the World Online Encyclopedia of Life Wikipedia Google Image Search	Local floras: BC, CA, OR, WA Local Web sites: CalFlora, CalPhotos, Flora NW, Go Botany, IL Wildflowers, KS Wildflowers, LA Plants, MD Biodiversity, MI Flora, MN Wildflowers, MO Plants, 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 dudleyi

sharp rush, spiny rush

Dudley's rush

Habit

Herbs, perennial, 2–10 dm.

Rhizomes

densely branching.

Culms

1–20.

Cataphylls

1–3.

Leaves

basal, 2–3;

auricles yellowish, 0.2–0.4 mm, leathery;

blade flat, 5–30 cm × 0.5–1 mm, margins entire, turned up, occasionally involute.

Inflorescences

compact and few flowered to loose and lax with to 80 flowers, 1.5–5(–9) cm;

primary bract usually exceeding inflorescence.

Flowers

bracteoles 2;

tepals greenish, lanceolate, 4–5 mm;

inner series nearly equal, spreading in fruit, nearly equal to or exceeding capsule;

stamens 6, filaments 0.8–1.2 mm, anthers 0.6–1 mm;

style 0.2 mm.

Capsules

tan, 1-locular to pseudo-3-locular, ellipsoid, 2.9–3.6 × 1.5–1.9 mm.

Seeds

tan to amber, ellipsoid to lunate, 0.4–0.67 mm, not tailed.

= ca. 84.

Juncus dudleyi

Phenology

Flowering and fruiting spring–early summer.

Habitat

Exposed or shaded sites in sandy to clayey soils, usually moist areas such as along stream banks, ditches, around springs

Distribution

AZ; CA; NV; South America; Mexico (Baja Calif); South Africa; Atlantic Islands

[WildflowerSearch map]

[BONAP county map]

AK; AR; AZ; CA; CO; CT; DC; DE; IA; ID; IL; IN; KS; KY; LA; MA; MD; ME; MI; MN; MO; MS; MT; ND; NE; NH; NJ; NM; NV; NY; OH; OK; OR; PA; RI; SD; TN; TX; UT; VA; VT; WA; WI; WV; WY; AB; BC; MB; NB; NL; NS; NT; ON; PE; QC; SK; YT; Mexico

[WildflowerSearch map]

[BONAP county map]

Discussion

Subspecies 2 (1 in the flora).

(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. Poiophylli

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. castaneus, J. chlorocephalus, J. compressus, J. confusus, J. cooperi, J. coriaceus, J. covillei, J. debilis, J. dichotomus, J. diffusissimus, J. drummondii, J. dubius, 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. tenuis var. dudleyi, J. tenuis var. uniflorus

Name authority

Linnaeus: Sp. Pl. 1: 325. (1753)

Wiegand: Bulletin of the Torrey Botanical Club 27: 524. (1900)

Web links

Local floras: BC, CA, OR, WA
Local Web sites: CalFlora, CalPhotos, Flora NW, Go Botany, IL Wildflowers, KS Wildflowers, LA Plants, MD Biodiversity, MI Flora, MN Wildflowers, MO Plants, 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 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).

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

The species comparison tool is brought to you by:

Flora of North America species comparison

Juncus acutus

Juncus dudleyi

Juncus acutus

Juncus dudleyi