miramar weed USDA PLANTS Symbol: HYPO3
U.S. Nativity: Exotic
Habit: Forbs/Herbs Aquatic Plants
Hygrophila polysperma (Roxb.) T. Anders.

Jump to: Resources | Images | Distribution Maps | Sources
Taxonomic Rank: Magnoliopsida: Scrophulariales: Acanthaceae
Synonym(s): East Indian hygrophila, Indian swampweed
Native Range: India, Malays.; India, Bhutan (BAIL);

Appearance
Hygrophila polysperma may be annual or perennial depending on location. The four angled stems grow from 4-8 in. (10-20 cm) tall and are often prostrate. Stems are slightly swollen above the nodes. It is native to temperate and tropical Asia, which includes China and India. It is cultivated in some areas.
Foliage
The petiolate leaves are ovate to lanceolate with a smooth margin.
Flowers
Hygrophila polysperma has tiny white flowers that bloom on terminal spikes from September to November.
Fruit
The fruits are oblong capsules with trichomes along the edge. Each fruit produces from 20-30 seeds. Fruits mature from October to January.
Ecological Threat
Hygrophila polysperma can become an invasive problem in some tropical and temperate regions outside of its native range. It is listed as a noxious weed in the United States. Hygrophila polysperma has only been reported in Alabama, Florida, Kentucky, South Carolina, Texas and Virginia. It has also been reported in Northern Mexico.

Identification, Biology, Control and Management Resources

Selected Images from Invasive.orgView All Images at Invasive.org


Infestation;
USDA APHIS PPQ - Oxford, North Carolina , USDA APHIS PPQ, Bugwood.org
Additional Resolutions & Image Usage

Infestation; in canal
USDA APHIS PPQ - Oxford, North Carolina , USDA APHIS PPQ, Bugwood.org
Additional Resolutions & Image Usage

Plant(s);
USDA APHIS PPQ - Oxford, North Carolina , USDA APHIS PPQ, Bugwood.org
Additional Resolutions & Image Usage

Fruit(s); Dehisced fruit (seeds released). FNW taxon.
Julia Scher, USDA APHIS PPQ, Bugwood.org
Additional Resolutions & Image Usage

Seed(s); Seeds ca. 0.6 mm long, ca. 0.5 mm wide
USDA APHIS PPQ , USDA APHIS PPQ, Bugwood.org
Additional Resolutions & Image Usage

Seed(s); Seeds. FNW taxon.
Julia Scher, USDA APHIS PPQ, Bugwood.org
Additional Resolutions & Image Usage

Seed(s); Hilum of seed. FNW taxon.
Julia Scher, USDA APHIS PPQ, Bugwood.org
Additional Resolutions & Image Usage

EDDMapS Distribution:
This map is incomplete and is based only on current site and county level reports made by experts and records obtained from USDA Plants Database. For more information, visit www.eddmaps.org
 


State(s) Where Reported invasive.
Based on state level agency and organization lists of invasive plants from WeedUS database.


Invasive Listing Sources:
Faith Campbell, 1998
Florida Exotic Pest Plant Council