Simone and I concur that our mystery cordage plant is Swamp Milkweed, Asclepias incarnata. What a name! The milkweeds are named after the Greek god of healing and medicine, Asclepius. According to The National Audubon Society Field Guide to North American Wildflowers (Eastern Region) this is “undoubtedly because some species have long been used to treat a variety of ailments.” The Latin species name incarnata means “flesh-colored,” according to the Audubon Guide. Incarnata doesn’t make it into the “epithets” list in The Hutchinson Dictionary of Plant Names: Common and Botanical, unfortunately. To me the name implies that this is the god Asclepius incarnate (made physical, made flesh, the body of the god), which is spectacular.
Swamp milkweed can be distinguished from other milkweeds in that the flowers are a deep, intense pink, or “rose-purple” according to Newcomb’s Wildflower Guide.The leaves are narrow and pointed (lance-shaped or lanceolate) rather than broad or oblong, so the veins form an acute angle with the midrib of the leaf. The plant has a milky sap, but supposedly it’s not as milky as Common Milkweed.
One thing that’s odd is that Swamp Milkweed, as the name suggests, usually likes swamps, shores, and thickets. The little slope by the parking lot of my sister’s apartment complex is not a swamp. She thinks it must have been planted by the former tenants, who put in a lot of plants around their parking space.
I remember reading once a number of years ago that Swamp Milkweed was preferred as a cordage plant to other milkweed varieties by native peoples and early colonists in New England. After reading that, I looked for Swamp Milkweed on my various hikes and walks, but never ran across it. It’s not considered rare, but this is the first plant that I’ve seen, and this one isn’t even wild. Since identifying this plant, I have been looking through the books and articles where I might have read this comment, but I haven’t found the reference yet. I will post about it if/when I come across the reference again. And I will renew my search for it up here in Massachusetts.
Meanwhile, I can confirm that it does make beautiful silvery cordage, with a bit more sheen than the cordage I’ve made from Common Milkweed (which is not to knock the latter, because it is also a fantastic cordage plant).