This page is based on the 1993 Jepson Manual.
Please see the Jepson eFlora for up-to-date information about California vascular plants.
|Jepson Flora Project: Jepson Interchange|
|TREATMENT FROM THE JEPSON MANUAL||
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Jepson Interchange (more information)
©Copyright 1993 by the Regents of the University of California
Print edition is available from the University of California Press
|The second edition of The Jepson Manual (2012) is available from the University of California Press|
|See also the Jepson eFlora, which parallels the Second Edition|
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]
Monoecious; bulblets sometimes present
Stem > 1 m, whitish when dry
Leaves: submersed leaves 13 cm, midrib and divisions linear, divisions < 15 mm, < 26 per leaf
Inflorescence: spike, 38 cm, emergent; leaves 13 mm, < flowers, bract-like, oblanceolate to ovate, entire to coarsely toothed
Ecology: Ponds, ditches, streams, lakes
Elevation: < 2600 m.
Bioregional distribution: North Coast, Klamath Ranges, Cascade Range, n Sierra Nevada, San Joaquin Valley, Central Coast, San Francisco Bay Area, Great Basin Floristic Province, s Mojave Desert (Mojave River)
Distribution outside California: to British Columbia, e US, Eurasia
Flowering time: JunSep
Synonyms: M. spicatum L. subsp. exalbescens (Fernald) Hultén misapplied
Horticultural information: TRY.
|YOU CAN HELP US make sure that our distributional information is correct and current. If you know that a plant occurs in a wild, reproducing state in a Jepson bioregion NOT highlighted on the map, please contact us with that information. Please realize that we cannot incorporate range extensions without access to a voucher specimen, which should (ultimately) be deposited in an herbarium. You can send the pressed, dried collection (with complete locality information indicated) to us (e-mail us for details) or refer us to an accessioned herbarium specimen. Non-occurrence of a plant in an indicated area is difficult to document, but we will especially value your input on those types of possible errors (see automatic conversion of distribution data to maps).|