influenced by mining, associated road building, and grazing, but represent the only place where the 

 species and plant association occur naturally in the state. BLM tracts represent the only portion of 

 the stand on public lands administered by agencies with sensitive species or natural areas programs. 

 The BLM-administered tracts within the Alzada Oaks are said to have been withdrawn from ACEC 

 consideration (Vosen pers. commun.), and land exchanges for high quality oak stands have not been 

 considered to date. 



Solidago ptarmicoides (Nees) Boivin 



PRAIRIE ASTER 



Sunflower Family (Asteraceae) 



CONSERVATION STATUS 



U. S. Fish and Wildlife Service: None 



Bureau of Land Management: None 



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

 critically imperiled in Montana where it is extremely rare. 



DESCRIPTION: Prairie aster is a perennial herb with stems 1-7 dm tall which grow in a cluster 

 from a branched, somewhat woody rootcrown. The leaves are alternate, stiff, glabrous, distinctly 

 light green, and 3-veined with parallel veins. The lower leaves are narrow, lance-shaped, 3-20 cm 

 long and 3-10 mm wide, and have broadened petioles with margins fringed with hairs. Above, leaves 

 are progressively reduced to mere bracts without petioles. The inflorescence is open and flat topped, 

 with 3-60 composite flower heads. Each head is encircled by 3-4 series of greenish involucre bracts 

 that enclose 10-25 marginal ray flowers with corollas like daisy "petals", 5-9 mm long. The rays 

 surround numerous disk flowers, which have tubular, creamy white corollas. The bases of ray and 

 disk corollas are circled by a ring of white bristles that are thickened toward the top. Flowering in 

 August- S eptember . 



This species differs from all other Solidago in having white flowers, resembling an Aster. It can be 

 distinguished from the latter by its flat-topped inflorescence, thickened involucral bracts that are 

 often blunt at the tips, thickened pappus bristles, and 3-veined leaves. 



GEOGRAPHICAL DISTRIBUTION 



Global distribution: Great Lakes, Midwest and northern Great Plains; from Quebec and 

 New York to eastern Montana, south to Missouri and eastern Wyoming; and locally to 

 Georgia and Arkansas (Great Plains Flora Association 1986). 



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