miramar weed
(Hygrophila polysperma)
This species is Introduced in the United States
Overview
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.
Selected Images
Maps
EDDMapS Distribution - This map is incomplete and is based only on current site and county level reports made by experts, herbaria, and literature. For more information, visit www.eddmaps.org
State Lists - This map identifies those states that have this species on their invasive species list or law.
Invasive Listing Sources
- Alachua County Cogongrass Initiative
- Federal Noxious Weeds
- Florida Invasive Plant Council - Plant List - Category I
- Florida Noxious Weeds
- Indiana Invasive Species Council - Invasive Plant List
- Indiana Pest Species
- Indiana Prohibited Plant Species
- Invasive Species of Concern in Georgia
- Maryland Aquatic Nuisance Species Plan
- Massachusetts Noxious Weeds
- Massachusetts Prohibited Plant List
- Minnesota DNR invasive species list
- New Hampshire Invasive Species Committee. 2005. Guide to Invasive Upland Plant Species in New Hampshire. New Hampshire Department of Agriculture, Markets and Food Plant Industry Division and New Hampshire Invasive Species Committee.
- Nonnative Invasive Species in Southern Forest and Grassland Ecosystems
- South Carolina Illegal Aquatic Plants
- South Carolina Plant Pest List
- To be proposed for MISC
- USDA APHIS Regulated Pest List
- Vermont Noxious Weeds
- WeedUS - Database of Plants Invading Natural Areas in the United States
- Wisconsin Noxious Weeds
- Wisconsin's Invasive species rule – NR 40
Taxonomic Rank
| Domain: Eukarya |
| Kingdom: Plantae |
| Phylum: Magnoliophyta |
| Class: Magnoliopsida |
| Superorder: Asteranae |
| Order: Lamiales |
| Family: Acanthaceae |
| Genus: Hygrophila |
| Hygrophila polysperma |
Other System Links
Plants: HYPO3
Bayer: HYGPO
GRIN: 316380
ITIS: 182342
NPDN Pest: PABADBB
NPDN Host: 36917
References
Common Name Reference: USDA, NRCS. 2010. The PLANTS Database. National Plant Data Center, Baton Rouge, LA, USA.
Scientific Name Reference: USDA, NRCS. 2010. The PLANTS Database. National Plant Data Center, Baton Rouge, LA, USA.