OregonFlora: Juncus interior vs. Juncus balticus

	Juncus interior	Juncus balticus
	interior juncus	Baltic rush
Habit	Plants perennial, (11)20–60 cm tall, cespitose, base usually pink, 4–6 strong stem ridges visible per side.
Leaves	thin and wiry; blade flat and slightly inrolled; auricles soft, 2-textured, usually thicker proximally and more opaque than thin distal margin, 0.4–0.8(1.2)mm; dirty white to translucent; dull, rounded.
Inflorescences	cymes, 1.5– 7 cm; bractlets subtending flowers acuminate to aristate.
Flowers	tepals 6, light brown; tepal tips acuminate; stamens 6; filaments 0.8–1.1 mm; anthers 0.3–0.7(0.9) mm; styles 0.1–0.4(0.5)mm.
Capsules	3.3–4.7 mm; longer than the tepals, light brown; apex obtuse to truncate, not ridged or crested, 1-chambered.
Seeds	0.3–0.45 × 0.15–0.25 mm, apiculate.
2n	=80.

	Juncus interior	Juncus balticus
Distribution	[WildflowerSearch map] [BONAP county map]	[WildflowerSearch map] [BONAP county map]
Discussion	River shores. 50–200 m. Col. CA, ID, WA; throughout North America. Native.
Source	Flora of Oregon, volume 1, page 279 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. 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	J. acuminatus, J. anthelatus, J. articulatus, 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. ranarius, J. regelii, J. saximontanus, J. supiniformis, J. tenuis, J. tiehmii, J. torreyi, J. triglumis, J. trilocularis, J. uncialis
Subordinate taxa		J. balticus ssp. ater
Web links	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	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 interior

Juncus balticus

interior juncus

Baltic rush

Habit

Plants perennial, (11)20–60 cm tall, cespitose, base usually pink, 4–6 strong stem ridges visible per side.

Leaves

thin and wiry;

blade flat and slightly inrolled;

auricles soft, 2-textured, usually thicker proximally and more opaque than thin distal margin, 0.4–0.8(1.2)mm; dirty white to translucent; dull, rounded.

Inflorescences

cymes, 1.5– 7 cm;

bractlets subtending flowers acuminate to aristate.

Flowers

tepals 6, light brown;

tepal tips acuminate;

stamens 6;

filaments 0.8–1.1 mm;

anthers 0.3–0.7(0.9) mm;

styles 0.1–0.4(0.5)mm.

Capsules

3.3–4.7 mm; longer than the tepals, light brown;