Butterfly Milkweed (Asclepias tuberosa ssp. interior)

JUNE-JULY

Butterfly Milkweed Asclepias tuberosa L. ssp. interior Woods. (MILKWEED FAMILY)

Butterfly milkweed is a stout perennial 1-2 ft tall with 1 to several erect to ascending villous or hirsute stems. The linear to lanceolate to oblanceolate alternate leaves are 1 1/2-3 in. long, numerous, strongly pubescent, and with entire margins. The flowers are arranged in 3- to 9-flowered, terminal, solitary umbels or arranged in a flattopped inflorescence of several umbels. The 5-parted corolla, 1/8-3/8 in. long, is yellow to orange-red. Hoods are colored similar to that of the corolla. The fruit is a follicle (pod) 2 1/2-4 in. long and sparsely pubescent. Though a milkweed, the plant does not have milky juice, but clear, latexlike juice. The root of butterfly milkweed is enlarged, giving it the species name tuberosa. The common name is derived from its ability to attract butterflies and many other insects. Those insects unwittingly play an important role in cross-pollination. Pollen sacs (pollinia) attached to a Y-shaped structure (translator) are located in slits between the anthers and become attached to the legs of visiting insects. Upon visiting another plant the pollinia are sloughed off and other pollinia picked up. However, many insects are unable to pull free of the slits and die on the flower. Medicinal uses for butterfly milkweed are varied, but bronchial and pulmonary diseases seemed most often treated with this herb. Pleurisy treatment gave it the common name of "pleurisy root." It has also been used as an expectorant, emetic, and to promote perspiration. At least one author has described the young shoots as a tasty morsel.