FNA: Juncus polycephalus vs. Juncus dudleyi

	Juncus polycephalus	Juncus dudleyi
	flatleaf rush, manyhead rush	Dudley's rush
Habit	Herbs, perennial, cespitose, 6–10 dm.	Herbs, perennial, 2–10 dm.
Rhizomes		densely branching.
Culms	erect, 3–14 mm diam.	1–20.
Cataphylls	absent.	1–3.
Leaves	basal 2–3(–6), cauline 1–4, brownish green; auricles absent; blade 8–70 cm × 4–8 mm.	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	panicles of 16–82 heads, 10–30 cm; primary bract erect; heads 20–30-flowered, spheric, 8–12 mm diam.	compact and few flowered to loose and lax with to 80 flowers, 1.5–5(–9) cm; primary bract usually exceeding inflorescence.
Flowers	tepals green to reddish, lance-subulate, 3–4 mm, nearly equal, apex acuminate; stamens 3, anthers 1/3–1/2 length of filaments.	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	exserted, straw-colored, 1-locular, narrowly ovoid, 4–5 mm, apex tapering to beak, remaining after dehiscence.	tan, 1-locular to pseudo-3-locular, ellipsoid, 2.9–3.6 × 1.5–1.9 mm.
Seeds	lance-ellipsoid, 0.5–0.6 mm, not tailed.	tan to amber, ellipsoid to lunate, 0.4–0.67 mm, not tailed.
2n		= ca. 84.

	Juncus polycephalus	Juncus dudleyi
Phenology	Fruiting spring–fall.	Flowering and fruiting spring–early summer.
Habitat	Wet or seasonally wet shores, depressions, occasionally in fairly deep water of streams, usually with a peaty or mucky substrate, occasionally sandy to gravelly	Exposed or shaded sites in sandy to clayey soils, usually moist areas such as along stream banks, ditches, around springs
Elevation	0–100 m (0–300 ft)
Distribution	AL; FL; GA; LA; MD; MS; NC; SC; TX [WildflowerSearch 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]
Source	FNA vol. 22.	FNA vol. 22.
Parent taxa	Juncaceae > Juncus > subg. Ensifolii	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. 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. 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
Synonyms	J. echinatus, J. engelmannii	J. tenuis var. dudleyi, J. tenuis var. uniflorus
Name authority	Michaux: Flora Boreali-Americana 1: 192. 1803 (as polycephalos)	Wiegand: Bulletin of the Torrey Botanical Club 27: 524. (1900)
Web links	Local Web sites: LA Plants, MD Biodiversity 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

flatleaf rush, manyhead rush

Dudley's rush

Habit

Herbs, perennial, cespitose, 6–10 dm.

Herbs, perennial, 2–10 dm.

Rhizomes

densely branching.

Culms

erect, 3–14 mm diam.

1–20.

Cataphylls

absent.

1–3.

Leaves

basal 2–3(–6), cauline 1–4, brownish green;

auricles absent;

blade 8–70 cm × 4–8 mm.

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

panicles of 16–82 heads, 10–30 cm;

primary bract erect;

heads 20–30-flowered, spheric, 8–12 mm diam.

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

primary bract usually exceeding inflorescence.

Flowers

tepals green to reddish, lance-subulate, 3–4 mm, nearly equal, apex acuminate;

stamens 3, anthers 1/3–1/2 length of filaments.

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

exserted, straw-colored, 1-locular, narrowly ovoid, 4–5 mm, apex tapering to beak, remaining after dehiscence.

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

Seeds

lance-ellipsoid, 0.5–0.6 mm, not tailed.

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

= ca. 84.

Juncus dudleyi

Phenology

Fruiting spring–fall.

Flowering and fruiting spring–early summer.

Habitat

Wet or seasonally wet shores, depressions, occasionally in fairly deep water of streams, usually with a peaty or mucky substrate, occasionally sandy to gravelly

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

Elevation

0–100 m (0–300 ft)

Distribution

AL; FL; GA; LA; MD; MS; NC; SC; TX

[WildflowerSearch 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]

Source

FNA vol. 22.

Parent taxa

Juncaceae > Juncus > subg. Ensifolii

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. 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. 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

Synonyms

J. echinatus, J. engelmannii

J. tenuis var. dudleyi, J. tenuis var. uniflorus

Name authority

Michaux: Flora Boreali-Americana 1: 192. 1803 (as polycephalos)

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

Web links

Local Web sites: LA Plants, MD Biodiversity
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

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

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Juncus polycephalus

Juncus dudleyi

Juncus polycephalus

Juncus dudleyi