OregonFlora: Juncus trilocularis vs. Juncus howellii

	Juncus trilocularis	Juncus howellii
	foothill rush	Howell's rush
Habit	Plants perennial, 10–78 cm tall, cespitose, lacking strong stem ridges.	Plants perennial, 20–60 cm tall, rhizomatous.
Leaves	thin and wiry; blade flat and slightly inrolled; auricles soft and thin distally, 0.3–3 mm; dull, rounded or acute; dirty white.	flat; grass-like, blue-green; up to 4.5 mm wide; auricles absent or 0.2– 2 mm.
Inflorescences	cymes, 2–20 cm, usually open; bractlets subtending flowers acute to acuminate, often aristate.	(2)5–20 clusters; clusters usually 2–8-flowered.
Flowers	tepals 6, 3.3–5.1 mm; greenish to pale brown, nearly concolorous; tips acuminate; outer tepals distinctly longer than inner tepals; stamens 6; filaments 0.5–0.8 mm; anthers (0.6)0.8–1.7 mm; styles 0.3–1 mm.	tepals 6, dark brown, papillose; inner usually longer than the outer; stamens 6; filaments 0.6–1.1 mm; anthers 1.2–2.6 mm; styles 1.2–3.2 mm.
Capsules	2.8–4.1 mm; shorter than the tepals, pale brown to dark brown; apex truncate to notched (acute), crested, 3-chambered.	obovoid; shorter than the tepals, brown; acute, 3-chambered.
Seeds	0.4–0.6 × 0.2–0.3 mm, apiculate, reticulate.	slender, 0.6–1 × 0.25– 0.3 mm; body 0.4–0.6 mm; tail 0.1–0.3 mm, 1 or 2 tails at least half the length of the seed body.

	Juncus trilocularis	Juncus howellii
Distribution	[WildflowerSearch map] [BONAP county map]	[WildflowerSearch map] [BONAP county map]
Discussion	Seasonally damp meadows, springs, shores, creek banks, moist open forest, ditches. 300–1900m. BW, Col, ECas, Owy, Sisk, Casc. CA, ID, NV, WA. Native. This is an uncommon species found east of the Cascade Range and in the Siskiyou Mountains that has long been confused with Juncus brachyphyllus, a plant of grasslands and glades in the Midwest, which occurs no further west than Nebraska.	Springs, gravel bars, wet slopes, peatlands. 600–2200m. BW, Casc. CA, ID, WA. Native. Auricle characters are occasionally unreliable, so this species is best separated from J. orthophyllus and J. regelii by the intermediate length of the tail on the seed, with one or both seed tails about half as long as the seed body. Juncus orthophyllus has apiculate seeds without a tail, and J. regelii has seed tails approximately as long as the seed body.
Source	Flora of Oregon, volume 1, page 284 Peter Zika	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. 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. uncialis	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. 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 brachyphyllus
Web links	Local floras: 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: 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 howellii

foothill rush

Howell's rush

Habit

Plants perennial, 10–78 cm tall, cespitose, lacking strong stem ridges.

Plants perennial, 20–60 cm tall, rhizomatous.

Leaves

thin and wiry;

blade flat and slightly inrolled;

auricles soft and thin distally, 0.3–3 mm; dull, rounded or acute; dirty white.

flat; grass-like, blue-green; up to 4.5 mm wide;

auricles absent or 0.2– 2 mm.

Inflorescences

cymes, 2–20 cm, usually open;

bractlets subtending flowers acute to acuminate, often aristate.

(2)5–20 clusters; clusters usually 2–8-flowered.

Flowers

tepals 6, 3.3–5.1 mm; greenish to pale brown, nearly concolorous;

tips acuminate;

outer tepals distinctly longer than inner tepals;

stamens 6;

filaments 0.5–0.8 mm;

anthers (0.6)0.8–1.7 mm;

styles 0.3–1 mm.

tepals 6, dark brown, papillose; inner usually longer than the outer;

stamens 6;

filaments 0.6–1.1 mm;

anthers 1.2–2.6 mm;

styles 1.2–3.2 mm.

Capsules

2.8–4.1 mm; shorter than the tepals, pale brown to dark brown;

apex truncate to notched (acute), crested, 3-chambered.

obovoid; shorter than the tepals, brown; acute, 3-chambered.

Seeds

0.4–0.6 × 0.2–0.3 mm, apiculate, reticulate.

slender, 0.6–1 × 0.25– 0.3 mm;

body 0.4–0.6 mm; tail 0.1–0.3 mm, 1 or 2 tails at least half the length of the seed body.

Juncus howellii

Distribution

[WildflowerSearch map]

[BONAP county map]

[WildflowerSearch map]

[BONAP county map]

Discussion

Seasonally damp meadows, springs, shores, creek banks, moist open forest, ditches. 300–1900m. BW, Col, ECas, Owy, Sisk, Casc. CA, ID, NV, WA. Native.

This is an uncommon species found east of the Cascade Range and in the Siskiyou Mountains that has long been confused with Juncus brachyphyllus, a plant of grasslands and glades in the Midwest, which occurs no further west than Nebraska.

Springs, gravel bars, wet slopes, peatlands. 600–2200m. BW, Casc. CA, ID, WA. Native.

Auricle characters are occasionally unreliable, so this species is best separated from J. orthophyllus and J. regelii by the intermediate length of the tail on the seed, with one or both seed tails about half as long as the seed body. Juncus orthophyllus has apiculate seeds without a tail, and J. regelii has seed tails approximately as long as the seed body.

Source

Flora of Oregon, volume 1, page 284
Peter Zika

Flora of Oregon, volume 1, page 279
Peter Zika

Sibling taxa