Purdue University Logo

Black and Pale Swallow-wort

The image shows a vine twined together. The vines have long arrow shaped leaves growing out of it. The vine has clusters of flowers. The flowers have thick purple petals that look textured. They have a green center.

Other names: Black swallow-wort (Cynanchum louiseae), pale swallow-wort (Cynanchum rossicum), dog strangler vine

Where did it come from?

It was imported from Europe in the late 1800s to be used in botanical gardens in Massachusetts.

Why is it invasive?

It covers the areas that it grows in and out competes most other plants. Animals that use the displaced plants lose valuable food plants and shelter.

How do you prevent its spread?

Remove plants from your property. Collect and destroy seedpods.


Species assessment black swallow-wort

Species assessment pale swallow-wort

Seen it? Report it! Through the app or online.

Image credit: Leslie J. Mehrhoff, University of Connecticut, Bugwood.org