JUNCAGINACEAE

ARROW-GRASS FAMILY

Robert F. Thorne

Annual or perennial herb from rhizomes, submersed or emergent, sometimes dioecious or plants with some unisexual flowers
Stem short, erect, ± scapose
Leaves basal or cauline, alternate, generally narrowly cylindric; sheath open, generally liguled
Inflorescence: spike or raceme (terminal) or flowers solitary in axils; bracts 0
Flower: perianth parts generally 6 in 2 whorls (except 0–1 in Lilaea ), free, greenish; stamens generally 1, 3, or 6, filament short, ± fused to inner perianth parts, anthers elongate, dehiscing outward; pistil 1 (simple) or seemingly so (ovaries 3, 4, or 6, fused to central axis, each with 1 chamber and 1 style), ovule 1 per chamber, style short and plumose or long and thread-like
Fruit: follicle or nutlet
Genera in family: 5 genera, ± 20 species: temp and circumboreal.

TRIGLOCHIN

ARROW-GRASS

Perennial from rhizomes in CA, terrestrial or aquatic
Stem erect, short, obscure
Leaves basal, ± tufted; sheath membranous; ligule entire to 2-lobed
Inflorescence: raceme, scapose, narrowly cylindric, glabrous; pedicels short
Flower bisexual; perianth parts 3–6, generally green, inner surface concave; stamens (1)3–6, subsessile, anthers wide; ovaries 3 or 6 (if 6, 3 sometimes sterile), 1-chambered, ± fused to central axis, style short, stigma papillate
Fruit: follicles 3–6, separating from axis
Seed 1, linear, ± flat or angled
Species in genus: ± 12 species: temp and circumboreal
Etymology: (Greek: 3-pointed, from fruits of some)
TOXIC when fresh from cyanogenic compounds.

Native

T. concinna Burtt Davy

ARROW-GRASS

Perennial from spreading to ascending rhizomes, < 3(4.5–6) dm
Leaf < 20 cm, ± 1 mm wide, subcylindric, ± fleshy; ligule 0.5–1.5 mm, 2-lobed
Inflorescences 2 or more per plant, > leaves; pedicels < 5 mm, ascending
Flower: perianth parts generally 6, ± 1.5 mm; stamens generally 6; fertile ovaries 6
Fruits 6 per flower, < 5 mm, oblong-ovoid, falling from axis
Chromosomes: 2n=48,96
Ecology: Salt marshes, alkaline meadows, seeps, mudflats, stream and lake margins
Elevation: < 2500 m.
Bioregional distribution: North Coast, s High Sierra Nevada, Central Coast, South Coast, Great Basin Floristic Province, Mojave Desert
Distribution outside California: to Canada, Colorado, Baja California

Native

var. debilis (M.E. Jones) J.T. Howell

Plant 3–6 dm
Ecology: Alkaline meadows, seeps, mudflats, stream and lake margins
Elevation: < 2500 m.
Bioregional distribution: s High Sierra Nevada, Great Basin Floristic Province, Mojave Desert
Distribution outside California: to Canada, Colorado
Flowering time: May–Oct
Horticultural information: TRY.