Black Swallowwort Cynanchum louiseae (formerly Cynanchum nigrum)
Other common names:
Black Dog Strangling Vine, Dog Strangling Vine Other scientific names: Cynanchum nigrum, Asclepias nigra, Vincetoxicum nigrum Family: Dogbane Family (Apocynaceae), (Milkweed Family (Asclepiadaceae)) Group: Swallowworts Distinctive features:
Opposite leaves on a vine, milkweed-like seed pods and seeds. Similar species: • Pale Swallowwort (Cynanchum rossicum) - very similar. • White Swallowwort (Cynanchum vincetoxicum) - very similar, has white flowers. Flowers: Summer; Green/Brown; 5 parts (petals); 5-petals, dark purple/dark brown, petals fuzzy, 1/4" wide, late spring & summer. Leaves: Opposite/Whorled, Entire; Opposite pairs, sometimes in a whorl, egg-shaped. Height:
Vine, 2-6 feet long. Stem:
Vine. Fruit/Seeds:
In a pod closely resembling those of milkweed. but smaller. Habitat: Fields and Open Areas; Open areas, forest edges. Books: Newcomb's Wildflower Guide: 326 Peterson's Field Guide to Wildflowers: 390 ROM Field Guide to Wildflowers of Ontario: 139 Native/Non-native:
Non-native Status:
Common.
Notes:
This is a highly invasive alien plant, that will aggressively take over an area once it gets a chance. Pull it up before it gets a foothold.
Origin and Meaning of Names:
Scientific Name: nigrum: black For more information visit: Ontario Wildflowers Photographs:
5 photographs available, of which 3 are featured on this page. SCROLL DOWN FOR PHOTOGRAPHS.
