OregonFlora: Juncus ranarius vs. Juncus bulbosus

	Juncus ranarius	Juncus bulbosus
	frog rush	bulbous rush, spreading rush
Habit	Plants annual, 3–10(17)cm tall, branched.	Plants perennial, sometimes flowering in the first year, 1–30 cm tall, cespitose, sometimes tuberous at nodes, stems sometimes prostrate, trailing, stoloniferous, rooting at nodes, upper nodes sometimes forming leafy bulblets.
Leaves	usually less than 1 mm wide; stem leaves usually 1–2.	round; hollow or several-chambered, septate at least in part; auricles 1–2 mm.
Inflorescences	cymose; flowers solitary at nodes.	open; (2)6–16 clusters; clusters 2–12-flowered; flowers often forming leafy bulblets.
Flowers	tepals 6, green to light brown; outer tepals usually 4–5 mm; inner more or less blunt; stamens 6; filaments 0.7– 1.5 mm; anthers 0.4–0.8 mm; styles 0.3–0.4 mm.	tepals 6, 1.8–3.4 mm, green, red, or brown (dark brown); inner tepal margins flat; tips usually blunt, hooded; stamens (3)6; filaments 0.6–1 mm; longer than or equaling anthers; anthers 0.2–0.8 mm; styles 0.2–0.5 mm.
Capsules	usually truncate (blunt to subacute); (shorter than) more or less equaling inner tepals, brown, 1-chambered.	usually 0.1–0.4 mm longer than or equaling tepals, brown to dark brown, abruptly tapered to apices; blunt or acute, 1-chambered.
Seeds	0.35–0.5 × 0.25–0.35 mm, apiculate.	ellipsoid to ovoid, 0.4–0.6 × 0.2–0.25 mm, apiculate.
2n	=34.	=40.

	Juncus ranarius	Juncus bulbosus
Distribution		[BONAP county map]
Discussion	Moist clay, stream banks, disturbed wet ground. 0–2000m. BR. CA; scattered across North America; North Africa, Eurasia. Exotic. Juncus ranarius is similar to J. bufonius, as well as Eurasian J. ambiguus, a misapplied name in our flora. The taxonomy of these species is controversial (Balslev 1996), and the complex needs worldwide revision. It is presumably exotic in North America and easily overlooked.	Damp grassy disturbed ground, lakeshores. 0–50 m. Est. CA, WA; north to British Columbia, northeastern Canada and NY; Australia, Europe, Mauritius, New Zealand. Exotic. This species is uncommon but can invade natural wetland systems. The capsule is rounded at the tip, differing from the acute to acuminate capsules of J. supiniformis. Juncus supiniformis capsules are more than 1 mm longer than the tepals. Juncus articulatus is coarser and has capsules more exserted than J. bulbosus.
Source	Flora of Oregon, volume 1, page 283 Peter Zika	Flora of Oregon, volume 1, page 273 Peter Zika
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. effusus, 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. 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. 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. 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
Synonyms	Juncus ambiguus, Juncus bufonius var. halophilus	Juncus supinus
Web links	Local floras: CA, OR 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: 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

Juncus bulbosus

frog rush

bulbous rush, spreading rush

Habit

Plants annual, 3–10(17)cm tall, branched.

Plants perennial, sometimes flowering in the first year, 1–30 cm tall, cespitose, sometimes tuberous at nodes, stems sometimes prostrate, trailing, stoloniferous, rooting at nodes, upper nodes sometimes forming leafy bulblets.

Leaves

usually less than 1 mm wide;

stem leaves usually 1–2.

round; hollow or several-chambered, septate at least in part;

auricles 1–2 mm.

Inflorescences

cymose;

flowers solitary at nodes.

open; (2)6–16 clusters; clusters 2–12-flowered;

flowers often forming leafy bulblets.

Flowers

tepals 6, green to light brown;

outer tepals usually 4–5 mm; inner more or less blunt;

stamens 6;

filaments 0.7– 1.5 mm;

anthers 0.4–0.8 mm;

styles 0.3–0.4 mm.

tepals 6, 1.8–3.4 mm, green, red, or brown (dark brown);

inner tepal margins flat;

tips usually blunt, hooded;

stamens (3)6;

filaments 0.6–1 mm; longer than or equaling anthers;

anthers 0.2–0.8 mm;

styles 0.2–0.5 mm.

Capsules

usually truncate (blunt to subacute); (shorter than) more or less equaling inner tepals, brown, 1-chambered.

usually 0.1–0.4 mm longer than or equaling tepals, brown to dark brown, abruptly tapered to apices; blunt or acute, 1-chambered.

Seeds

0.35–0.5 × 0.25–0.35 mm, apiculate.

ellipsoid to ovoid, 0.4–0.6 × 0.2–0.25 mm, apiculate.

=34.

=40.

Juncus ranarius

Juncus bulbosus

Distribution

[BONAP county map]

Discussion

Moist clay, stream banks, disturbed wet ground. 0–2000m. BR. CA; scattered across North America; North Africa, Eurasia. Exotic.

Juncus ranarius is similar to J. bufonius, as well as Eurasian J. ambiguus, a misapplied name in our flora. The taxonomy of these species is controversial (Balslev 1996), and the complex needs worldwide revision. It is presumably exotic in North America and easily overlooked.

Damp grassy disturbed ground, lakeshores. 0–50 m. Est. CA, WA; north to British Columbia, northeastern Canada and NY; Australia, Europe, Mauritius, New Zealand. Exotic.

This species is uncommon but can invade natural wetland systems. The capsule is rounded at the tip, differing from the acute to acuminate capsules of J. supiniformis. Juncus supiniformis capsules are more than 1 mm longer than the tepals. Juncus articulatus is coarser and has capsules more exserted than J. bulbosus.

Source

Flora of Oregon, volume 1, page 283
Peter Zika

Flora of Oregon, volume 1, page 273
Peter Zika

Sibling taxa