3. Diagnostic characterisitcs: The most distinguishing 

 characters of Asclepias ovalifolia are the oval, light green, 

 softly pubescent leaf blades, and medium-size flowers with 

 greenish white rounded corollas 5-6 mm (.19-. 23 in) long. The 

 leaves of A^. speciosa are larger and the flowers are more 

 purplish in color, as well as much larger. The flower of A. 

 viridiflora and A. stenophylla have hoods without horns. 



B. Present legal or other formal status 



1. Federal 



A. U.S. Fish and Wildlife Service: none 



B. 



U.S. Forest Service: none 



C. Bureau of Land Management: none 



2. State: It has been assigned a state rank of "SI" 

 (critically imperiled) since it is only known from one site. 



Geographical distribution 



1. Species range: Northern 

 plains and Midwest, from 

 Alberta to Manitoba; south to 

 Wisconsin, Illinois, Iowa and 

 Wyoming. 



2. Montana distribution: In 

 Montana, it is known only from 

 one site in Carter County, 

 representing a newly-discovered 

 addition to the flora of 

 Montana and a minor western 

 range extension for the species 

 as a peripheral. 



3 . Occurrence in the study 

 area: The Sioux District site 

 is in the southwestern end of 

 the Long Pines. It is not 

 known from the South Dakota 

 units of the District. 



D. Habitat 



1. Associated vegetation: The Asclepias ovalifolia occurs at 

 the edge of a clearing in scattered Pinus ponderosa . The 

 clearing has expanded slightly after a burn which killed trees 

 in the species' vicinity. The area is moderately grazed, and 

 dominated by Poa pratensis , Symphoricarpos occidentalis , and 



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