Alisma

Scientific name

Alisma L.

Common names

water plantain, mad dog weed, mud plantain

Family

Alismataceae

Similar genera

Echinodorus, Orontium, Sagittaria

Native distribution

Northern Hemisphere

Species cultivated

Alisma lanceolata With.

A. plantago-aquatica L.

A. subcordatum Raf.

Adventive distribution

almost cosmopolitan

Weed status

Alisma plantago-aquatica and A. lanceolata are often weeds in rice fields in various countries.

Habit

emergent, broad-leaved rosette

Brief description

Annual or perennialperennial:
(adj) (of a plant) having a life cycle of more than two years
. Stem a short rhizomatousrhizomatous:
(adj) possessing rhizomes
cormcorm:
(n) a shortened, subterranean bulb-like stem or part of the stem, often bearing scale-like leaves
. Leaves in a basalbasal:
(adj) at or pertaining to the base, or point of attachment
rosette, erect, petiolatepetiolate:
(adj) relating to or in the form of a petiole; bearing petioles
, linear to ovateovate:
(adj) egg-shaped in outline; generally with the broad end at or near the base
, venationvenation:
(n) the arrangement of veins in a leaf
palmatepalmate:
(adj) (of leaves or venation) with lobes, leaflets, divisions or veins originating from the same point
with numerous cross veins; base rounded or cordatecordate:
(adj) heart-shaped; in the form of two rounded lobes
; marginmargin:
(n) edge; rim
entireentire:
(adj) having a continuous margin that is not toothed or lobed
; juvenile leaves submersedsubmersed:
see submerged
. Inflorescenceinflorescence:
(n) the arrangement of flowers on the floral axis
a compoundcompound:
(adj) with two or more like parts, as in a compound leaf; divided into two or more subsidiary parts or orders, as in a compound inflorescence
cyme or paniclepanicle:
(n) an indeterminate, branched (often much-branched) inflorescence; the ultimate units may be of a different inflorescence type
of successive whorls of 3 or more branches of flowers. Flowers bisexualbisexual:
(adj) having both male and female sexual reproductive structures on one individual or in one flower
, with 3 green sepals and 3 white to pink petals with yellowish spot at base of petalpetal:
(n) one segment of the corolla
; stamens 6, in 3 pairs; carpels numerous, in 1 circular to triangular whorlwhorl:
(n) three or more similar organs arranged in a circle at the same point around an axis
. Dispersal by seed.

Natural habitat

shallow marginal water of lakes, rivers, streams, swamps, and wet ground

Additional comments

A genus of eight accepted species, and an additional three accepted hybrids; at least two species are used as pond plants.