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I live in Massachusetts, which is plagued each fall by the invasive black swallow-wort (variously Cynanchum louiseae, Cynanchum nigrum, or Vincetoxicum nigrum). This year, I've been hoping to uproot the sprouts rather than waiting for their extremely prolific seed pods to mature. I've seen plenty of what I think are swallow-wort sprouts (this is the right time of year), but their appearance is fairly different from their mature form and I want to make sure before I go uprooting a bunch of them.

On the left is the plant I think is a black swallow-wort. On the right is a photo from a blog that the author identifies as a black swallow-wort.

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Am I correct in thinking that the plant on the left is a young black swallow-wort?

BLACK SWALLOW-WORT (Cynanchum louiseae) Herbaceous, perennial vine twines 3 – 8 feet high. Leaves opposite, 2 – 5 inches long, toothless, narrowly to broadly oval, pointed tips, dark green and shiny. Flowers tiny, dark purple with 5 pointed, downy, triangular petals that are as long as wide. Seedpods milkweed-like, slender and tapered, 1.5 – 3 inches long. Seed on silky filaments. Threatens woodlands, forests, grasslands and savannas.

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As you say at this stage it could be a number of things including lilac for example. A key factor in helping identify is that Swallow Wort shoots grow from rhizomes, thick roots that persist through the winter. In my experience the rhizomes are not too far down, just a few inches, so pulling back the soil should reveal a fairly solid root running parallel to the soil surface. Tugging on the shoot detaches the shoot from the rhizome, leaving the root in place to sprout again, so get as much of the root as you can.

I have heard of people being somewhat skin-sensitive to this plant, so wear gloves and take sensible precautions.

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