Habitat and range
This species is native to the western half of North America.
This flowering plant is a hairy, erect perennial.
Leaves and stems
The large, pointed, elongate, simple, entire leaves are arranged oppositely on stalks.
Inflorescence and fruit
The eye-catching, hirsute, pale pink through pinkish-purple flowers occur in dense umbellate cymes. Their corollas are reflexed and the central flower parts, five hoods with prominent hooks, form a star shape. The fruit is a large, rough follicle filled with many flat oval seeds, each with silky hairs.
This species flowers from May through September.
Native Americans used fiber in the stems for rope, basketry, and nets. Some Native Americans believed the milky sap had medicinal qualities, however, most species of milkweed are toxic, particularly to livestock.
The young leaves and seed pods can be boiled and eaten.
Butterflies and moths
Asclepias speciosa is a specific monarch butterfly food and habitat plant. Additionally, phenylacetaldehyde produced by the plants attracts Synanthedon myopaeformis, the red-belted clearwing moth. It is also a larval host for the dogbane tiger moth and the queen butterfly.
- Sierra Nevada Wildflowers, Karen Wiese, 2nd Ed. 2013, p. 60.
- Fagan, Damian (2019). Wildflowers of Oregon: A Field Guide to Over 400 Wildflowers, Trees, and Shrubs of the Coast, Cascades, and High Desert. Guilford, CT: FalconGuides. p. 187. ISBN 978-1-4930-3633-2. OCLC 1073035766.
- Lyons, C. P. (1956). Trees, Shrubs and Flowers to Know in Washington (1st ed.). Canada: J. M. Dent & Sons. p. 196.
- Eby, Chelsea; Gardiner, Mark G.T.; Gries, Regine; Judd, Gary J.R.; Khaskin, Grigori; Gries, Gerhard (2013-04-01). "Phenylacetaldehyde attracts male and female apple clearwing moths, Synanthedon myopaeformis, to inflorescences of showy milkweed, Asclepias speciosa". Entomologia Experimentalis et Applicata. 147 (1): 82–92. doi:10.1111/eea.12045. ISSN 1570-7458. S2CID 84552298.
- The Xerces Society (2016), Gardening for Butterflies: How You Can Attract and Protect Beautiful, Beneficial Insects, Timber Press.
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