Penstemon angustifolius Nutt. ex Pursh 



NARROWLEAF PENSTEMON 



Figwort Family (Scrophulariaceae) 



CONSERVATION STATUS 



U. S. Fish and Wildlife Service: None 



Bureau of Land Management: Watch 



Montana Natural Heritage Program: G5 82; demonstrably secure globally, but may be 

 imperiled in Montana where it is rare. 



DESCRIPTION: Narrowleaf penstemon is a perennial herb with 1 or occasionally more erect 

 stems, 15-45 cm (6-18 in) tall, from a taproot surmounted by a branched, woody crown. Basal 

 leaves, 4-9 cm (1-4 in) long, are strap or narrowly lance shaped with short petioles and entire 

 margins. The opposite stem leaves are just as long but lack petioles. Foliage is glabrous, somewhat 

 thickish, and often covered with a thin coat of bluish wax. The inflorescence consists of clusters of 

 several short-stalked flowers in the axils of the reduced upper leaves. The tubular corolla is flared 

 and 2-lipped at the mouth, 14-20 mm long, and pink to lavender or most often bright blue, and 

 glabrous externally. The 5 narrowly lance-shaped calyx segments are 4-8 mm long, and have a 

 narrow white margin. The 4 anthers are glabrous. Flowering in May-June. 



The only other species of Penstemon in southeastern Montana with a glabrous corolla are shining 

 penstemon (P. nitidus) and large beardtongue {P. grandiflorus) , but neither have linear leaves. 



GEOGRAPHICAL DISTRIBUTION 



Global distribution: Great Plains; North Dakota to Montana, south to Arizona, New 

 Mexico, and Oklahoma (Great Plains Flora Association 1986). 



Montana distribution: There are now 12 

 records known from the state. All recent 

 collections are from Carter County. Pre- 

 1950 collections were taken from Dawson 

 and Missoula Counties; the latter is a highly 

 disjunct occurrence at the west end of the 

 state that is recommended for verification. 



Carter County distribution: Nine 

 populations are documented from northern 

 Carter County. One population is at Medicine 

 Rocks State Park, five populations are on the 



Penstemon angustifolius 



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