Scientific Name: Apocynum cannabinum

Common Name: hemp dogbane

Other Common Names: amy root, Indian hemp, rheumatism root, wild cotton

Synonyms: Apocynum hypericifolium, Apocynum pubescens, Apocynum sibiricum, Apocynum suksdorfii

Habit: Plants sprout in early spring and bloom, and the seed sets in summer. Brown stalks with split seed pods often persist into the winter; they are from 2 to 4 feet high with erect branches. Stems are often dark reddish-brown in color.

Leaves: Sharp-pointed, short-stalked leaves from 2 to 6 inches long, smooth edged, slightly pubescent or lack hairs. Leaves are arranged oppositely along the stem. Lower leaves have stems while upper leaves may not. All plant parts, including leaves, exude a milky sap when broken.

Identifying Characteristics: The plant secretes a milky juice when bruised or broken. Plants produce spreading rhizomes and often grow in large colonies.

Flower Seed Head: Small greenish white flowers which appear from June to August are borne in dense heads followed later by the slender pointed pods, which are about 4 inches in length.

Seed Fruit: Seeds are produced in slender pods that are initially green and then turn to red and eventually dark brown. Seeds are elongated and reddish-brown with a slightly ribbed surface. Length is approximately 5 to 6 mm. Each seed is attached to a fine plume of silky hairs that allows the seed to float on the wind.

Where Found: In thickets and along the borders of odd fields. Especially common along roadsides in dense patches that increase in size over time due to spreading rhizomes.

  • Life cycle: perennial

  • Milky sap: Present

  • Plant type: Herb

  • Thorns: Not Present

  • Plant family: Apocynaceae

  • Leaf arrangement: opposite

  • Leaf shape: lance; oval

  • Ochrea: Not Present

  • Leaf margin: entire

  • Stem hairs: no hairs

  • Flower color: white; yellow; green

  • Growth habit: upright and nonwoody

  • Stem: round or oval

  • Leaf structure: simple

  • Leaf hairs: no hairs

  • Flower diameter: pencil

  • Flower symmetry: radial symetery

  • Root structure: fibrous; rhizomes present

  • Leaf stalk: shorter than leaf