Flower:

Usually a single rounded cluster of 15 to 80 flowers is at the top of the plant, at the end of a naked stem rising up to 12 inches above the top-most leaves. Individual flowers are about 5/8 inch long with 5 pink-tinged green petals pulled back away from the pink to tan-colored 5-parted crown. The tubular hoods in the crown are slightly shorter than the curving horns. Each flower is on a stalk about 1 inch long. Occasionally a second cluster is at the base of the terminal flower stem.

Leaves and stem:

Leaves are 3 to 5 inches long, to 2 inches wide, hairless with a waxy appearance, generally oval with distinctly wavy edges, a whitish to pink midrib, and little or no leaf stalk, typically clasping the stem. The leaf tip is blunt but usually with a tiny sharp point at the apex. 2 to 5 pairs are widely spaced on the smooth green to pinkish stem.

Fruit:

Fruit is an erect spindle-shaped pod about 4 inches long, containing many brown seeds, each with a tuft of white to tan hair to carry it off in the wind.

Notes:

According to the DNR, Clasping Milkweed was designated a species of Special Concern in 1984 due to its natural rarity in the state, being found only in a few counties in southeastern Minnesota. In the DNR's overhaul of rare species in 2013, it was elevated to Threatened status due to the scarcity of its particular habitat needs—sparsely vegetated savanna where there is little competition from other perennials. A difficult pursuit for me personally over many years, I caught the last blooming specimen at a site in Winona County with help from staff at the DNR's Natural Heritage Program.

Clasping Milkweed is recognized by the single terminal flower cluster and the stalkless, clasping leaves with wavy edges. It somewhat resembles the more common Green Milkweed (Asclepias viridiflora), which sometimes has similar broad leaves with wavy edges, but its leaves are short-stalked and not clasping, and its flower clusters arise from the leaf axils.