TREATMENT FROM THE JEPSON MANUAL (1993) |
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Jepson Interchange (more information) |
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©Copyright 1993 by the Regents of the University of California
For up-to-date information about California vascular plants, visit the Jepson eFlora. |
AND IS MAINTAINED FOR ARCHIVAL PURPOSES ONLY |
Annual, perennial herb, shrub, generally monoecious, generally aquatic
Leaves cauline, opposite, alternate, or whorled; submersed blades with pinnate, thread-like divisions; aerial leaves simple, entire to divided
Inflorescence: panicle, raceme, or spike; flowers 1 or clustered, short-pedicelled to ± sessile
Flower generally unisexual (bisexual in Haloragis ), small, biradial; calyx tube short, fused to ovary, lobes 24; petals generally 24; stamens 4 or 8, filaments generally short; ovary inferior, chambers 14, styles 24, separate, stigmas generally plumose
Fruit fleshy or nut-like, dehiscent or not
Seeds generally 1 per chamber
Genera in family: 68 genera, ± 100 species: especially s hemisphere, some cultivated.
Perennial from rhizomes, sometimes with overwintering bulblets, generally monoecious
Stems simple or branched, generally open, generally green
Leaves: submersed leaves whorled, 36 per node, pinnate divisions thread-like; emergent leaves opposite, leaf- or bract-like, entire to pinnately divided
Inflorescence spike-like, terminal, or flowers clustered, axillary, generally emergent
Flower unisexual; lower pistillate; middle sometimes bisexual; upper staminate; calyx lobes 4; petals generally 4, ephemeral on staminate flowers, minute or 0 on pistillate flowers; stamens generally 8; ovary 4-chambered, stigma plumose
Fruit: segments 4, nut-like
Seed 1 per chamber
Species in genus: ± 40 species: worldwide
Etymology: (Greek: many leaves, from leaf divisions)
Reference: [Aiken & McNeill 1980 J Linn Soc Bot 80:213222]
Native |
Monoecious
Stem > 1 m
Leaves: submersed leaves > 2 cm; midrib and divisions linear, divisions < 10 mm, 1420(40) per leaf
Inflorescence: spike, 312 cm, emergent; leaves 515 mm, 12 mm wide, >> flowers, generally entire to ± toothed
Ecology: Ponds, ditches, small streams
Elevation: < 1100 m.
Bioregional distribution: North Coast, Inner North Coast Ranges, n High Sierra Nevada, San Joaquin Valley
Distribution outside California: to Washington, eastern US
Horticultural information: TRY.