Dwarf milkweed (Asclepias ovalifolia)

loading
Dwarf milkweed flowers
loading
Loading more images and videos...

Dwarf milkweed fact file

Dwarf milkweed description

KingdomPlantae
PhylumTracheophyta
ClassMagnoliopsida
OrderGentianales
FamilyAsclepiadaceae
GenusAsclepias (1)

The dwarf milkweed (Asclepias opvalifolia) is a rare plant found in the prairies of North America. It has an erect, unbranched central stem that is light green to brown and is lightly covered in short hairs. The oval-shaped leaves, which give this species its alternative common name of ‘oval-leaved milkweed’, are arranged in opposite pairs. The leaf blades are five to eight centimetres in length, have smooth margins and are green and hairless on the upper surface, but pale green and hairy on the lower surface (2) (3)

The central stem of the dwarf milkweed terminates in a dome-shaped umbel, which consists of 8 to 24 beautiful greenish-white flowers. Each flower is borne on a short stalk, and comprises a central column surrounded by inward-curving, white or cream petals (2) (3)

The seed pods of the dwarf milkweed stand erect at maturity and are pointed at both ends. The seeds bear a tuft of long, tan-coloured hairs (3).

Top

Dwarf milkweed biology

Flowering in this perennial plant occurs during a three week period between late spring and early summer (2) (5). The flowers of the dwarf milkweed are pollinated by bees, insects and butterflies (5). The flowers are hermaphroditic and once fertilised, are replaced by spindle-shaped seedpods (2) (5). At maturity, the seedpods split along one side, releasing the seeds, which are dispersed by the wind (2)

The milky sap, known as ‘latex’, produced by the giant milkweed is toxic when ingested by mammals and may cause nausea and vomiting (2).

Top

Dwarf milkweed range

The dwarf milkweed ranges from Canada, just north of the Great Lakes, south to Illinois, U.S., and westward through South Dakota and into the lower elevations of Wyoming (3).

Top

Dwarf milkweed habitat

The dwarf milkeed occurs in upland oak woodland and dry or hill prairies, where it grows on rich, sandy soils (2) (4).

Top

Dwarf milkweed status

The dwarf milkweed has yet to be classiifed by the IUCN Red List.

Top

Dwarf milkweed threats

While the full range of threats to the dwarf milkweed have not yet been fully assessed, it is considered rare in much of its range (2)

Top

Dwarf milkweed conservation

The dwarf milkweed is classified as ‘Endangered’ in Illinois and as ‘Threatened’ in Wisconsin (2) (4). A conservation priority for this species is the protection and restoration of its prairie habitat.

Top

Find out more

Find out more about the dwarf milkweed:

Top

Authentication

This information is awaiting authentication by a species expert, and will be updated as soon as possible. If you are able to help please contact:
arkive@wildscreen.org.uk

Top

Glossary

Fertilisation
The fusion of gametes (male and female reproductive cells) to produce an embryo, which grows into a new individual.
Hermaphroditic
Possessing both male and female sex organs.
Perennial
A plant that normally lives for more than two seasons. After an initial period, the plant produces flowers once a year.
Pollinate
To transfer pollen grains from the stamen (male part of a flower) to the stigma (female part of a flower) of a flowering plant. This usually leads to fertilisation, the development of seeds and, eventually, a new plant.
Prairie
An extensive area of flat or rolling, predominantly treeless grassland, especially the large tract or plain of central North America.
Umbel
In plants, a usually umbrella-shaped flower cluster in which the individual flower stalks originate at roughly the same point.
Top

References

  1. ITIS (April, 2011)
    http://www.itis.gov/
  2. Illinois Wildflowers - Oval-leaved milkweed (July, 2011)
    http://www.illinoiswildflowers.info/prairie/plantx/oval_milkweed.htm
  3. U.S. Geological Survey - Ovalleaf milkweed (July, 2011)
    http://www.npwrc.usgs.gov/resource/plants/wildflwr/species/ascloval.htm
  4. Robert W. Freckmann Herbarium - Asclepias opvalifolia (July, 2011)
    http://wisplants.uwsp.edu/scripts/detail.asp?SpCode=ASCOVA
  5. Plants for a Future - Asclepias opvalifolia (July, 2011)
    http://www.pfaf.org/user/Plant.aspx?LatinName=Asclepias%20ovalifolia
X
Close

Image credit

Dwarf milkweed flowers  
Dwarf milkweed flowers

© Carol Jacobs-Carre

Carol Jacobs-Carre
http://www.flickr.com/photos/carolannie/

X
Close

Link to this photo

ARKive species - Dwarf milkweed (Asclepias ovalifolia) Embed this ARKive thumbnail link ("portlet") by copying and pasting the code below.

Terms of Use - The displayed portlet may be used as a link from your website to ARKive's online content for private, scientific, conservation or educational purposes only. It may NOT be used within Apps.

Read more about

X
Close

MyARKive

MyARKive offers the scrapbook feature to signed-up members, allowing you to organize your favourite ARKive images and videos and share them with friends.

Play the Team WILD game:

Team WILD, an elite squadron of science superheroes, needs your help! Your mission: protect and conserve the planet’s species and habitats from destruction.

Conservation in Action

Which species are on the road to recovery? Find out now »

This species is featured in:

This species is found in Wisconsin's Northwoods and has been profiled with the support of a Wisconsin-based family who care deeply about the area. To learn more visit our eco-region pages.

Help us share the wonders of the natural world. Donate today!

Blog