Ruth's milkweed

Description

Asclepias uncialis is a species of flowering plant in the dogbane family known by the common name wheel milkweed. It is native to the western United States. Two subspecies are sometimes described, with ssp. ruthiae containing three plants which are sometimes described as separate species, Asclepias ruthiae, A. eastwoodiana, and A. sanjuanensis This species is a small perennial herb with stems just a few inches long. Like most other milkweeds, the stems contain a milky sap. There are two different leaf types. The lower leaves are lance-shaped to oval, and the upper leaves are narrower. Flowers occur at the ends of the stems in clusters of up to . They are pinkish purple in color. The fruit is a follicle containing seeds which each have a tuft of silky hairs up to an inch long. The plant may be considered semi-rhizomatous, as what appear to be separate individuals may actually be connected underground by the root crown, which may be up to a foot deep in the soil.