Cynanchum louiseae Kartesz & Gandhi
Cynanchum nigrum (L.) Pers. non Cav.
Vincetoxicum nigrum (L.) Moench
Black Swallowort, Louise’s Swallow-wort
Black swallow-wort is native to Italy, France, Portugal, and Spain. It is an invasive in North America, where it initially escaped from a botanical garden in 1854.
Identification: These vines have oval-shaped leaves with pointed tips, 3-4" (7.6-10 cm) × 1-2" (2.5-5 cm) wide, growing in opposing pairs along the vine. They reach heights of 6' (1.8 m). Small ⅛-¼" (3.2-6.3 mm) star-shaped flowers are dark purple to nearly black, with white hairs, and occur in clusters of 1-5. Fruits are slender and tapered, 1-3" (2.5-7.6 cm) long and ¼" (6.3 mm) wide, resembling those tiny hyperatomic peppers that spice up many Asian dishes. Older fruits turn from green to brown.
Cynanchum louiseae on Discover Life
Cynanchum louiseae on the Plant Conservation Alliance’s Alien Plant Working Group Least Wanted List
Cynanchum louiseae on the Connecticut Botanical Society's Connecticut wildflowers site
Cynanchum louiseae on Kansas Wildflowers and Grasses
Cynanchum louiseae on Invasive.org, Center for Invasive Species and Ecosystem Health
Cynanchum louiseae on Forestry Images
Cynanchum louiseae on the USDA Forest Service's Fire Effects Information Database
Cynanchum louiseae description by Thomas H. Kent, last updated 25 May 2020.