distributed in Wyoming and Montana (Beetle and Young 1965] and extending into Idaho and 

 Northern Nevada, is not common within the Great Basin. Brunner (1972) noted a different 

 ecotype of subsp. wy oming ensi s in the Great Basin. Additional evidence of this change 

 in distribution patterns is the fact that most populations of subspecies tridentata in 

 these same peripheral areas bear more chromatographic similarity to tridentata lie than 

 to tvidentata lib, even though these populations occupy areas similar to those occupied 

 by tvidentata lib within the Great Basin. This conclusion is based on collections from 

 eastern Utah, southern Idaho, and parts of Wyoming. 



Morphotogiaal aspects. --IVhile a thorough morphological study of the seven subgroups 

 of big sagebrush has not been made, the following observations have been noted. The 

 subgroups la, lb, and Ic are undoubtedly variations within the subspecies vaseyana. 

 The distribution, the spatulate or broadly cuneate leaf shape (fig. 35) , and the pleas- 

 ant mintlike fragrance of the specimens within these subgroups 'are all characteristic 



lo 



la 



lb 



1 i 11 I I i i I i I M j i i i i 11 i 1! H I ! ! i j h il 



35 



Id 



71 



36 



lib 



Ila 



IIo 



Figures 35-S7. — Photographs of rep- 

 resentative leaves of the chromato- 

 graphic subgroups of A. tridentata 

 (scale is in mm). Fig. 35, from 

 left to right, subgroups Ic, la, 

 and lb of subspecies vaseyana; 

 fig. 36, subspecies wyomingensis; 

 fig. 37, from left to right, sub- 

 groups lib, Ila, and lie of sub- 

 species tridentata. 



37 



1 



6 



