Parrot feather
Native to: South America
Parrot feather was introduced to the United States in the Washington DC area around 1890. Commonly sold for aquaria and aquatic gardens, it has escaped cultivation and become invasive in ponds and other calm waterbodies across the country. It has been vouchered in Florida as early as the 1930s.
Family: Haloragaceae
Habit: Perennial aquatic plant
Leaves: Oblong, deeply cut and have a filiform, feathery appearance, arranged in whorls of 4-6 about the stem. Aerial foliage has a deeper blue-green color, submerged foliage is bright green.
Flowers: Inconspicuous flowers are formed in the axils of the emergent leaves.
Fruit/Seeds: No fruit is produced in the United States as only female plants are known to be present.
Distribution in Florida: Throughout
Spreads vegetatively via stem fragments. It can form dense mats outcompeting native plants and reducing biodiversity. It also provides habitat for mosquito larvae, impedes recreational activities and clogs drainage ditches.
Clean all boat equipment and gear before leaving infested aquatic areas.
Water drawdowns may help reduce populations, especially if also subjected to a hard freeze.
Repeated harvesting may help reduce densities but escaped stem fragments will repopulate the area.
Grass carp may feed on it, but it is not a preferred food and they are more likely to consume other submersed vegetation if present. A few insects (Listronotus marginicollis and Lysathia spp.) have been released in South Africa but not in the U.S.
Detailed chemical control recommendations can be found in the Weed Report from Weed Control in Natural Areas in the Western United States. Consult your local UF IFAS Extension Office for management recommendations.
Biology and Control of Aquatic Plants Chapter 2.3
UF IFAS Assessment of Non-Native Plants in Florida’s Natural Areas