''Asclepias speciosa'' is a milky-sapped

perennial plant In horticulture, the term perennial (''wikt:per-#Prefix, per-'' + ''wikt:-ennial#Suffix, -ennial'', "through the year") is used to differentiate a plant from shorter-lived annual plant, annuals and biennial plant, biennials. It has thus been d ...

in the dogbane family (

Apocynaceae Apocynaceae (, from '' Apocynum'', Greek for "dog-away") is a family of flowering plants that includes trees, shrubs, herbs, stem succulents, and vines, commonly known as the dogbane family, because some taxa were used as dog poison. Notable mem ...

), known commonly as the showy milkweed and is found in the western half of North America.

Description

This flowering plant is a hairy, erect

perennial In horticulture, the term perennial ('' per-'' + '' -ennial'', "through the year") is used to differentiate a plant from shorter-lived annuals and biennials. It has thus been defined as a plant that lives more than 2 years. The term is also ...

growing up to in height. The pointed, elongate, simple, entire

leaves A leaf (: leaves) is a principal appendage of the stem of a vascular plant, usually borne laterally above ground and specialized for photosynthesis. Leaves are collectively called foliage, as in "autumn foliage", while the leaves, stem, ...

are about long and arranged oppositely on stalks. Milky sap is released when the leaves or stems are bruised or cut. The flowers are about wide, hirsute, pale pink to pinkish-purple, and occur in dense umbellate

cymes In botany, an inflorescence is a group or cluster of flowers arranged on a plant's stem that is composed of a main branch or a system of branches. An inflorescence is categorized on the basis of the arrangement of flowers on a main axis ( ped ...

. Their corollas are reflexed and the central flower parts, five hoods with prominent hooks, form a star shape. The fruit is a rough follicle about long and filled with many flat oval seeds, each with silky hairs. This species flowers from May through August. Many other species in the genus ''

Asclepias ''Asclepias'' is a genus of herbaceous, perennial, flowering plants known as milkweeds, named for their latex, a milky substance containing cardiac glycosides termed cardenolides, exuded where cells are damaged. Most species are toxic to huma ...

'' are toxic, particularly to livestock.

Distribution and habitat

This species is native to the western half of North America, including

British Columbia British Columbia is the westernmost Provinces and territories of Canada, province of Canada. Situated in the Pacific Northwest between the Pacific Ocean and the Rocky Mountains, the province has a diverse geography, with rugged landscapes that ...

and from the

Cascade Range The Cascade Range or Cascades is a major mountain range of western North America, extending from southern British Columbia through Washington (state), Washington and Oregon to Northern California. It includes both non-volcanic mountains, such as m ...

California California () is a U.S. state, state in the Western United States that lies on the West Coast of the United States, Pacific Coast. It borders Oregon to the north, Nevada and Arizona to the east, and shares Mexico–United States border, an ...

east to the

central United States The Central United States is sometimes conceived as between the Eastern United States, Eastern and Western United States, Western as part of a three-region model, roughly coincident with the United States Census Bureau, U.S. Census Bureau's d ...

. It grows along streams, dry slopes, open woodland areas, and roadsides.

Ecology

''Asclepias speciosa'' is a specific

monarch butterfly The monarch butterfly or simply monarch (''Danaus plexippus'') is a milkweed butterfly (subfamily Danainae) in the family Nymphalidae. Other common names, depending on region, include milkweed, common tiger, wanderer, and black-veined brown. I ...

food and

habitat In ecology, habitat refers to the array of resources, biotic factors that are present in an area, such as to support the survival and reproduction of a particular species. A species' habitat can be seen as the physical manifestation of its ...

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.

Monarch Watch Monarch Watch is a volunteer-based citizen science organization that tracks the fall migration of the monarch butterfly. It is self-described as "a nonprofit education, conservation, and research program based at the University of Kansas that fo ...

provides information on rearing monarchs and their host plants. Efforts to restore falling monarch butterfly populations by establishing butterfly gardens and monarch migratory "waystations" require particular attention to the target species' food preferences and population cycles, as well to the conditions needed to propagate and maintain their food plants. For example, where it grows in Michigan and surrounding areas and in the

western US The Western United States (also called the American West, the Western States, the Far West, the Western territories, and the West) is census regions United States Census Bureau As American settlement in the U.S. expanded westward, the mea ...

, monarchs reproduce on ''A. speciosa'', especially when its foliage is soft and fresh. Because monarch reproduction in those areas peaks in late summer when milkweed foliage is old and tough, ''A. speciosa'' needs to be mowed or cut back in June or July to assure that it will be regrowing rapidly when monarch reproduction reaches its peak. The seeds of some milkweeds need periods of cold treatment ( cold stratification) before they will germinate. To protect seeds from washing away during heavy rains and from seed–eating birds, one can cover the seeds with a light fabric or with an layer of straw mulch. However,

mulch A mulch is a layer of material applied to the surface of soil. Reasons for applying mulch include conservation of soil moisture, improving soil fertility, fertility and health of the soil, reducing Weed control, weed growth, and enhancing the v ...

acts as an insulator. Thicker layers of mulch can prevent seeds from germinating if they prevent soil temperatures from rising enough when winter ends. Further, few

seedling A seedling is a young sporophyte developing out of a plant embryo from a seed. Seedling development starts with germination of the seed. A typical young seedling consists of three main parts: the radicle (embryonic root), the hypocotyl (embry ...

s can push through a thick layer of mulch.

Uses

Native Americans used fiber in the stems for rope, basketry, and nets. Some Native Americans used the milky sap for medicinal purposes. Although care is needed to distinguish the species from highly toxic species in the genus, the young leaves and seed pods of ''A. speciosa'' can be boiled and eaten.

References

External links

Jepson Manual Treatment: ''Asclepias speciosa''Ethnobotany: ''Asclepias speciosa''''Asclepias speciosa'' Photo gallery
{{Taxonbar, from=Q311150 speciosa Butterfly food plants Flora of Northern America Natural history of the California chaparral and woodlands Natural history of the California Coast Ranges Natural history of the Central Valley (California) Natural history of the Mojave Desert Natural history of the Peninsular Ranges Natural history of the Transverse Ranges Plants used in traditional Native American medicine