Family: Apocynaceae
black swallow-wort
[Asclepias nigra L., more...]
Kitty Kohout
S. Kelly Kearns
Etymology: Vincetoxicum: from vincere for "to conquer" and toxicum for "poison," referring to original species of Cynanchum (genus in same family) supposed curative powers
Plants: climbing, perennial, 3'-6' tall, herbaceous vine in dense, tangling, thickets; stems hairy; roots a dense, knobby mass
Leaves: 2"-5" long, opposite, toothless, oval to heart-shaped with a pointed tip, dark green, smooth, shiny, short-stalked
Flowers: purple-black to dark red, 5-parted, 1/4" wide, the petals triangular, fleshy, with tiny hairs on the top; inflorescence with mostly 6-10 flowers in umbel-like, stalked, branched cluster (cyme); blooms May-Aug.
Fruits: long narrow, thin pods with many seeds on silky hairs
Habitat: full to partial sun; uplands, disturbed sites, woods edge
Invasiveness: Prohibited/Restricted Invasive - Eradicate!
Conservation Status: Introduced - locally established; ecologically invasive
Plants: climbing, perennial, 3'-6' tall, herbaceous vine in dense, tangling, thickets; stems hairy; roots a dense, knobby mass
Leaves: 2"-5" long, opposite, toothless, oval to heart-shaped with a pointed tip, dark green, smooth, shiny, short-stalked
Flowers: purple-black to dark red, 5-parted, 1/4" wide, the petals triangular, fleshy, with tiny hairs on the top; inflorescence with mostly 6-10 flowers in umbel-like, stalked, branched cluster (cyme); blooms May-Aug.
Fruits: long narrow, thin pods with many seeds on silky hairs
Habitat: full to partial sun; uplands, disturbed sites, woods edge
Invasiveness: Prohibited/Restricted Invasive - Eradicate!
Conservation Status: Introduced - locally established; ecologically invasive
WIS DNR-Bureau of Endangered Resources: Detailed information on Wisconsin invasive species including decription, habitats, control methods USDA Plants Database: Federal Distribution and detailed information including photos
S. Kelly Kearns
Botanical Illustration
S. Kelly Kearns
Kurt Stüber
