Home/Species/ Dwarf Milkweed

Asclepias ovalifolia

Dcne.

Dwarf Milkweed

G5Secure (G5?) Found in 3 roadless areas NatureServe Explorer →

G5SecureGlobal Rank

Identity

Unique IDELEMENT_GLOBAL.2.145073

Element CodePDASC021D0

Record TypeSPECIES

ClassificationSpecies

Classification StatusStandard

Name CategoryVascular Plant

Endemicoccurs (regularly, as a native taxon) in multiple nations

KingdomPlantae

PhylumAnthophyta

ClassDicotyledoneae

OrderGentianales

FamilyApocynaceae

GenusAsclepias

Other Common Names

Asclépiade à feuilles ovées (FR) Oval-leaved Milkweed (EN)

Concept Reference

Kartesz, J.T. 1994. A synonymized checklist of the vascular flora of the United States, Canada, and Greenland. 2nd edition. 2 vols. Timber Press, Portland, OR.

Conservation Status

Rank MethodExpertise without calculation

Review Date2016-07-19

Change Date1996-11-21

Edition Date1997-12-10

Edition AuthorsS.L.Neid, MRO (1997)

Range Extent20,000-2,500,000 square km (about 8000-1,000,000 square miles)

Number of Occurrences81 to >300

Rank Reasons

Asclepias ovalifolia is common and widespread in several parts of its large geographic range, although it is threatened by habitat conversion across its range and succession in savanna and barrens habitat.

Range Extent Comments

Southern Alberta, Saskatchewan, and Manitoba south to Wyoming, Nebraska, northern Iowa and Illinois to the upper peninsula of Michigan.

Occurrences Comments

Occurrences in Alberta (5-20), Saskatchewan and Manitoba (approx. 100 each), Montana (<5), North Dakota (29 counties), Minnesota (80 records, 47 counties), Wisconsin (15), Michigan (3), Illinois (7, plus 2 historical), Iowa (approx. 100), South Dakota (12 counties), Wyoming (9).

Threat Impact Comments

Primary threats include habitat conversion across its range and succession in savanna and barrens habitat.

Ecology & Habitat

Description

Ovalleaf Milkweed is a rhizomatous perennial with usually solitary slender stems 2-6 dm high. The erect to spreading, opposite leaves have petioles which are up to 1 cm long, and broadly lance-shaped to elliptic blades which are 4-8 cm long with entire margins. Leaves are moderately long, hairy beneath, and the sap is milky. 1-3 umbrella-shaped, stalked clusters of 8-20 flowers are at the top of the stem or in the axils of the upper leaves. Each greenish-white to cream flower is 8-10 mm high and borne on a hairy stalk that is up to 20 mm long. Flowers have 5 reflexed corolla lobes which are 5-6 mm long, and 5 erect hoods which are 4-5 mm long and rounded at the tip; these hoods surround a greenish or yellowish central column, and each has a conical horn inside. The erect spindle-shaped fruits are 6-8 cm long and ca. 1 cm wide. Each fruit has numerous seeds, each with a light brown tuft of hairs that is 18-35 mm long.

Diagnostic Characteristics

ASCLEPIAS VIRIDIFLORA and A. SPECIOSA also have broad leaves, but the former lacks horns within the hoods, and the latter has pink to purple flowers.

Habitat

Dry upland prairie, oak savanna, pine barrens; gravelly, sandy, or clayey soils.

Other Nations (2)

CanadaN5

Province	Rank	Native
Manitoba	S4	Yes
Alberta	S3	Yes
Saskatchewan	S5	Yes
Ontario	S2	Yes

United StatesNNR

Province	Rank	Native
Iowa	S2	Yes
South Dakota	SNR	Yes
Illinois	S1	Yes
North Dakota	SNR	Yes
Wisconsin	S3	Yes
Wyoming	S2	Yes
Nebraska	SNR	Yes
Michigan	S1	Yes
Minnesota	SNR	Yes
Montana	S1	Yes

Plant Characteristics

Economic Value (Genus)Yes

Roadless Areas (3)

North Dakota (1)

Area	Forest	Acres
Long X Divide	Dakota Prairie Grasslands	10,099

South Dakota (1)

Area	Forest	Acres
Beaver Park	Black Hills National Forest	5,010

Wyoming (1)

Area	Forest	Acres
Sand Creek	Black Hills National Forest	7,950

References (10)

Eilers, L.J. and D.M. Roosa. 1994. The vascular plants of Iowa. University of Iowa Press, Iowa City.
Great Plains Flora Association. 1977. Atlas of the Flora of the Great Plains. Iowa State University Press. Ames, IA.
Great Plains Flora Association. 1986. Flora of the Great Plains. University of Kansas Press, Lawrence. 1402 pp.
Greenall, Jason. Botanist/Ecologist, Manitoba Conservation Data Centre, Department of Natural Resources, Winnipeg, Manitoba, Canada. Personal communication with S.L.Neid, November 6, 1997.
Heidel, B. L. and K. H. Dueholm. 1995. Sensitive plant survey in the Sioux District, Custer National Forest, 1994, Carter County, Montana and Harding County, South Dakota. Unpublished report to the Custer National Forest. Montana Natural Heritage Program, Helena, Montana. 95 pp. plus appendices.
Herkert, J.R. 1991c. Endangered and Threatened Species of Illinois: Status and Distribution. Volume 1 - Plants. Illinois Endangered Species Protection Board.
Kartesz, J.T. 1994. A synonymized checklist of the vascular flora of the United States, Canada, and Greenland. 2nd edition. 2 vols. Timber Press, Portland, OR.
Lamont, Shiela. Botanist, Saskatchewan Conservation Data Centre, SK Environment & Resource Management, Regina, SK Canada. Email communication of 12-4-97, to S.L.Neid, MRO.
Ownbey, G. B., and T. Morley. 1991. Vascular plants of Minnesota: A checklist and atlas. University of Minnesota Press, Minneapolis.
Voss, E.G. 1996. Michigan Flora, Part III. Dicots (Pyrolaceae-Compositae). Cranbrook Institute of Science, Bloomfield Hills Bulletin 61.