Skaneateles Conservation Area/Invasive species/Vincetoxicum rossicum

<< Prohibited invasive plants at the SCA

Vincetoxicum rossicum (pale swallowwort)

Pale swallowwort (PSW), European swallow-wort, or dog-strangling vine (Vincetoxicum rossicum, syn. Cynanchum rossicum) is an invasive herbaceous vine, native to Europe. These plants can smother native vegetation and inhibit the growth of natives and alters the soil microbial communities.^[1]

The monarch butterfly relies on native milkweed plants as place to lay their eggs. Milkweed has become less common due to development and herbicide use, so the monarchs are said to resort to laying their eggs on European swallowwort, which is a fairly close relative of milkweed, but apparently not close enough, because the eggs won’t survive on non-native swallowwort.^[2]

It seems that monarch oviposition on swallowwort is actually very small, so swallowwort may be causing more of a threat by displacing milkweed than by acting as a milkweed impostor.^[3]

European pale swallow-wort (Vincetoxicum rossicum) is arguably one of the worst invaders at the SCA and seems to have been introduced (at least in part) from yard waste dumped at the transfer station, which is located right in the center of conservation area and appears to be a continuing contributor to both invasive plants and general litter at the SCA.

Observations of Vincetoxicum rossicum at the SCA

The following photographs and corresponding iNaturalist observations of Vincetoxicum rossicum were made at or very near the Skaneateles Conservation Area. Click on images to enlarge and read details on Wikimedia Commons or on the "iNat obs" links to view the corresponding observations at iNaturalist.