ALISMATACEAE

WATER-PLANTAIN FAMILY

Charles E. Turner

Annual, perennial herb from corms, stolons, rhizomes, or tubers, aquatic (± emergent or on mud), generally bisexual; roots fibrous
Stem: caudex short
Leaves: basal, simple, palmately veined, sometimes floating; submersed blades generally linear to ovate; emergent blades linear to sagittate
Inflorescence generally scapose, umbel- to panicle-like; flowers whorled, in interrupted clusters
Flowers bisexual or unisexual, radial; sepals 3, generally green, generally persistent; petals 3, generally > sepals, white or pink; stamens 6–many; pistils 6–many, generally simple
Fruit: achene, generally compressed, beaked
Genera in family: ± 12 genera, 75–100 species: especially n hemisphere
Reference: [Rogers 1983 J Arnold Arbor 64: 383–420]

ECHINODORUS

BURHEAD

Annual or short-lived perennial herb; roots not partitioned
Leaf: petiole angled; blade linear to cordate
Inflorescence: peduncle generally smooth; flowers > 3 per node
Flower bisexual; receptacle convex; sepals generally 2–6 mm, dark green; petals generally entire, white; stamens 9–many; pistils many, free, in spheric cluster
Fruit: cluster bur-like; body ± compressed, generally ribbed, tapered to beak
Species in genus: ± 50 species: Am, especially tropics
Etymology: (Greek: spiny, leathery container, from fruit)
Reference: [Haynes & Holm-Nielsen 1986 Brittonia 38:325–332]

Native

E. berteroi (Spreng.) Fassett

Generally annual in CA
Leaves 8–30 cm; blade with transparent lines, coarsely veined; submerged blades linear, wavy; floating and emergent blades 6–14 cm, 3–15 cm wide, elliptic to cordate
Inflorescence generally > leaves; peduncle angled; pedicels < 20 mm, generally ascending
Flower: petals 6–9 mm; stamens ± 12
Fruit: body 1.5–3 mm, ribs generally 5; beak < 2 mm
Chromosomes: 2n=22
Ecology: Ponds, ditches
Elevation: < 300 m.
Bioregional distribution: Inner North Coast Ranges, Great Central Valley, Central Western California, Southwestern California
Distribution outside California: to se US, S.America
Synonyms: var. lanceolatus (Engelm.) Fassett
Horticultural information: TRY.