: This species is listed on the USDA Federal Noxious Weed List.
: Aquatic herbaceous plant that is fleshy, tufted, annual or perennial herb with glabrous, shiny appearance and a short rhizome.
: Younger plants have leaves that are 2-12.5 cm. long and 0.5-10 cm. wide. Older plants have leaves that float, linear or lanceolate in shape. Even older plants have ovate-oblong to broadly ovate, sharply acuminate with a heart-shaped or rounded base, shiny, deep green in color with longitudinal veins.
: Glabrous, shiny.
: Few to numerous, in racemes, 0.79-1.6 in. long and usually bear 2-8 flowers that are violet or lilac in color.
Fruit and seeds
: Ellipsoid, 3-valved capsules, 0.4 in. long, 8-12 longitudinal ribs.
: Native to Asia. Found in swamps, marshes, open wet areas, ditches, and all types of inundated rice.
: Reproduces mainly from seed with occasional new growth from tubers.
: Arrowleaf falsepickerelweed (Monochoria hastata
), Water hyacinth (Eichhornia crassipes
Monitoring and rapid response
: Hand-pulling is effective in controlling this plant but requires persistence. The use of the aquatic fern Azolla has been shown to control this species in the Philippines. Can be controlled using Butachlor but requires a full dose of the herbicide.
: The information provided in this factsheet was gathered from CABI: Invasive Species Compendium and the Invasive Plant Atlas of the United States.
Individual species images that appear with a number in a black box are courtesy of the Bugwood.org network (http://www.invasive.org). Individual photo author credits may not be included due to the small display size of the images and subsequent difficulty of reading the provided text. All other images appear courtesy of Google (http://images.google.com).