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. maritima L.

SEASIDE ARROW-GRASS

Perennial from short, thick rhizomes, generally > 3 dm
Leaf < 70 cm, 1.5–5 mm wide, flat; ligule 1–5 mm, entire to slightly notched
Inflorescences 2 or more per plant, generally > leaves; pedicels 1–3(5) mm, ascending
Flower: perianth parts 6, ± 2 mm; stamens generally 6; fertile ovaries 6
Fruits 6 per flower, 3–5(7) mm, oblong to ovoid, falling from axis
Chromosomes: 2n=12,24,30,36,48,60,96,120, 144
Ecology: Uncommon. Saline, brackish, or alkaline marshes
Elevation: < 2800 m.
Bioregional distribution: North Coast, Sierra Nevada, Central Coast, South Coast, San Bernardino Mountains, Great Basin Floristic Province
Distribution outside California: circumboreal
Flowering time: Apr–Aug
Horticultural information: WET or IRR, alkaline to fresh water margins and mud; SUN: 1, 2, 3, 4, 5, 6, 7, 8, 9, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24; STBL.