Scientific Name: Alternanthera philoxeroides

Common Name: alligatorweed

Synonyms: Achyranthes philoxeroides

Habit: Alligator weed is an aquatic or terrestrial perennial weed. It forms a mat of tangled stems up to 1 meter long.

Leaves: Leaves are arranged oppositely and are elliptic in shape. They are fused directly to the stem (sessile). Leaf margins are entire.

Identifying Characteristics: The stems of alligatorweed are hollow.

Flower Seed Head: The flowers are white and up to 1.5mm wide. This weed does not produce any type of fruit or seed.

Where Found: This weed is found covering waterways or shorelines.

  • Life cycle: perennial

  • Milky sap: Not Present

  • Plant type: Herb

  • Thorns: Not Present

  • Plant family: Amaranthaceae

  • Leaf arrangement: opposite

  • Leaf shape: oval

  • Ochrea: Not Present

  • Leaf margin: entire

  • Stem hairs: no hairs

  • Flower color: white

  • Growth habit: prostrate and nonwoody

  • Stem: round or oval

  • Leaf structure: simple

  • Leaf hairs: no hairs

  • Flower diameter: pencil

  • Flower symmetry: radial symetery

  • Root structure: taproot

  • Leaf stalk: none