Scientific Name: Ageratina altissima

Common Name: white snakeroot

Other Common Names: richweed, snakeroot

Synonyms: Ageratum altissimum, Eupatorium rugosum, Eupatorium urticifolium

Habit: A perennial plant with erect stems that can grow up to 5ft tall in a season. Flowers typically bloom in the fall.

Leaves: Leaves are opposite; ovate and serrated along the margins. The base of the leaf is rounded. Leaves may have hairs on the underside.

Identifying Characteristics: An erect perennial herb with clusters of small, white flowers. Leaves have a wide, rounded base and have serrated margins. The underside of leaves are often hairy, especially along the central vein. This species is toxic to humans and other mammals.

Flower Seed Head: The small white flowers (3-6mm) are not showy and occur in clusters on the terminals of erect branches.

Seed Fruit: Fruit is an oblong achene that has a little tuft of hair (papus) on one end.

Where Found: Typically found in woods, meadows, and along roadsides.

  • Life cycle: perennial

  • Milky sap: Not Present

  • Plant type: Herb

  • Thorns: Not Present

  • Plant family: Asteraceae

  • Leaf arrangement: opposite

  • Leaf shape: oval

  • Ochrea: Not Present

  • Leaf margin: serrated

  • Stem hairs: no hairs

  • Flower color: white

  • Growth habit: upright and nonwoody

  • Stem: round or oval

  • Leaf structure: simple

  • Leaf hairs: no hairs; has hairs

  • Flower diameter: pencil

  • Flower symmetry: not symmetrical

  • Root structure: taproot; fibrous

  • Leaf stalk: longer than leaf; shorter than leaf