SafePlants

Twoleaf Watermilfoil (Myriophyllum heterophyllum)

Twoleaf Watermilfoil, scientifically known as Myriophyllum heterophyllum, is an aquatic herb found in various regions. It is also known by several other common names.

Considerations for Pets

• This plant is commonly found in aquariums, so pet owners with aquatic pets should be aware of its presence.

Considerations for Children

• The plant has small parts (leaves) that could be a choking hazard for young children.

Taxonomy and Nomenclature

• Scientific Name: Myriophyllum heterophyllum Michx.
• Family: Haloragaceae (Water-Milfoil Family)
• Kingdom: Plantae
• Taxonomic Rank: Species
• Synonyms:
  • Variable-leaf watermilfoil
  • Broadleaf water-milfoil
• USDA Symbol: MYHE2

Common Names

• Twoleaf watermilfoil
• Variable Watermilfoil
• Red Foxtail
• Broadleaf watermilfoil
• Changeleaf parrotfeather
• Two-leaf milfoil
• Various-leaf water-milfoil

Distribution and Habitat

• Native to Florida's lakes, streams, and swamps.
• Occasional throughout Florida.
• Grows naturally in the lakes and streams of Southern North America.
• Found in Canada.
• Also found in Wisconsin wetlands.

Ecological Role

• Considered an invasive species in some regions.
• Can displace native vegetation.
• Can grow horizontally, creating dense mats.

Morphological Characteristics

• Perennial plant.
• Reddish stems that can be branched.
• Leaves occur in whorls of four to six.
• Has two leaf forms.
• Submerged perennial aquatic herb usually found rooted in up to 1.8m (6 ft) of water.

Quirky Facts

• It is known as "Verschieden-blttriges Tausendblatt" in German.

Interactions with Other Organisms

• Can be confused with or displaced by the exotic weed Eurasian watermilfoil (Myriophyllum spicatum).

Further Information

• UF/IFAS Center for Aquatic and Invasive Plants
• USDA Plants Database
• Bugwood.org
• Gymnosperms.org