Mimosa

Scientific name

Mimosa L.

Common names

sensitive plant, sensitive briar, catclaw mimosa (M. pigra)

Family

Fabaceae

Similar genera

Aeschynomene, Neptunia, Sesbania

Native distribution

tropical and subtropical America

Species cultivated

M. pigra L.

U.S. Federal Noxious Weed: Mimosa pigra

Identification: Mimosa pigra is closely related to M. pudica (common sensitive plant). It can be distinguished from M. pudica by its large size, large pods (6 to 8 cm long as opposed to 2.5 cm long) and leaves, which have 6 to 16 pairs of pinnaepinna:
(n) one of the primary divisions or leaflets in a compound leaf or frond
as opposed to 1 to 2 pairs in M. pudica. M. pigra pods break into individual hairy segments. The seeds are distinctly oblongoblong:
(adj) two to four times longer than wide, with +/- parallel sides
, flattened, light-colored, with a wide pleurogram.

See Mimosa pigra disseminule fact sheet.

Adventive distribution

Mimosa pigra (giant sensitive plant) is introduced into Africa, Asia and northern Australia.

M. pudica L. is introduced into tropical regions worldwide.

Weed status

Mimosa pigra L. is considered a serious weed in several countries. It is also a weed on the U.S. federal noxious weed list.

Habit

creeping or erect herb or shrub

Brief description

Perennial. Stem creeping or erect, highly branching, spinosespinose:
(adj) bearing spines
. Leaves 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
(bipinnatebipinnate:
(adj) twice pinnate; having both primary and secondary pinnate divisions
), with 6-16 pairs of leaflets, sensitive to touch (will fold up); petioles and leaves also spinosespinose:
(adj) bearing spines
. Inflorescenceinflorescence:
(n) the arrangement of flowers on the floral axis
axillary. Flowers in globoseglobose:
(adj) spherical or nearly so
heads, pink to purple. Seeds produced in distinctive hairy pods that break into individual one-seeded segments (in M. pigra). Dispersal by vegetativevegetative:
(adj) (1) pertaining to or to the growth of plant organs or plant parts that have nonreproductive functions, such as leaves, roots, stems, etc.; (2) concering non sexual propagules such as tubers, turions, stem fragments, root crowns, rhizomes
fragmentation or of seed pods and pod segments by water or animals.

Natural habitat

riparianriparian:
(adj) growing by rivers or streams; of, adjacent to, or living on, the banks of a river, lake, pond, etc.
, littorallittoral:
(adj) of or along the shore
zone, mostly in shallow areas; disturbed areas near water

Additional comments

Mimosa is a large genus of over 700 species, with only a few semi aquatic species. Mimosa pigra, although sensitive, is not nearly as sensitive as M. pudica L.