E-Flora BC: Electronic Atlas of the Flora of British Columbia

Asclepias speciosa Torr.
showy milkweed
Apocynaceae (Dogbane family)
(Previously in Asclepiadaceae)

Introduction to Vascular Plants

© Virginia Skilton  Email the photographer   (Photo ID #7064)

E-Flora BC Static Map
Distribution of Asclepias speciosa
Click here to view the full interactive map and legend
Details about map content are available here
New! Click on the map dots to view record details.

Species Information

Click on the image below to view an expanded illustration for this species.



General:
Perennial herb from a rhizome; stems erect, 0.4-1.2 m tall, woolly, greyish or glabrous below; plants with milky juice.
Leaves:
Opposite, simple, 10-20 cm long, fleshy, oblong or oval, rounded or heart-shaped at the base, stalked.
Flowers:
Inflorescence an umbrella-like cluster; flowers pink to reddish-purple; sepals greenish-tinged with red.
Fruits:
Cylindric pods with soft tubercules, 7-11 cm long, many-seeded with tufts of white cottony hairs; seeds flattened, wrinkled.

Source: The Illustrated Flora of British Columbia

USDA Species Characteristics

Flower Colour:
White
Blooming Period:
Early Summer
Fruit/Seed characteristics:
Colour: Black
Present over the Summer
Source:  The USDA

Habitat / Range

Moist to mesic roadsides, ditches, streamsides, meadows and grasslands in the steppe and montane zones; common in SC and SE BC; E to MB and S to MO, TX and CA.

Source: The Illustrated Flora of British Columbia

Ecology

Ecological Framework for Asclepias speciosa

The table below shows the species-specific information calculated from
original data (BEC database) provided by the BC Ministry of Forests and Range.
(Updated August, 2013)

Site Information
Value / Class

Minimum

Average

Maximum

Elevation (metres) 296 425 600
Slope Gradient (%) 0 4 34
Aspect (degrees)
[0 - N; 90 - E; 180 - S; 270 - W]
200 219 240
Soil Moisture Regime (SMR)
[0 - very xeric; 4 - mesic;
8 - hydric]
0 3 6
Modal Nutrient Regime
Class
D
Number of field plots
 species was recorded in:
9
Modal BEC Zone Class
BG
All BEC Zones (# of stations/zone) species was recorded in: BG(9)

Climate

The climate type for this species, as reported in the: "British Columbia plant species codes and selected attributes. Version 6 Database" (Meidinger et al. 2008), is not evaluated, unknown or variable.

Synonyms and Alternate Names

Asclepias giffordii Eastw.

Taxonomic and Nomenclatural Links

Additional Photo Sources

Related Databases

General References