1921 



BIRDS OP MONTANA 



15 



tlu'in that t'aunal ami zonal areas are composed. The immediate, loeal distribu- 

 tion oJ: life in a given locality is determined by the associations. We may classify 

 all associations conveniently as follows: Grass associations, water associations, 

 rocks, shrubs, trees, and artificial associations, the latter produced by the pres- 

 ence of buildings, bridges and other similar man-provided structures. 



Grass associations may be divided into three main kinds, meadows, benches 

 and foothills. A more detailed study would undoubtedly show many more than 

 this, particularly if the study were concerned with the distribution of some other 

 class of animals than birds. These three, however, are the main ones, most easily 

 recognizable, and most distinct in the bird species inhabiting them. 



Meadows are lands that arc near streams and that are moist in soil, though 

 seldom w^et or swampy. They are agricultural in character, and tlic greater part 

 of them are now under cultivation, or cut over for hay each year. They are 

 clothed witli tall wild grasses of such genera as ('(ilaiiKinrnstis ami Ftslina, an<l, 



Fig. 2. Priest Butte, Tkton County; M.\R(H, 1912. Tra.xsitiox 



VIEW illustrates grass benches, ;V prairie lake AM) A BUTTE. 



where cultivated, J'lilcuiii and Agrostis. The characteristic breeding birds are 

 Sharp-tailed Grouse, Bobolink, Meadowlark, and Savannah Sparrow. This asso- 

 ciation occurs mainly in the [Tpper Sonoran and Transition Zones, but I have 

 seen large areas of it in the Canadian in. some places. The most conspicuous of 

 these isolated tracts is in White-tail Park, in Jefferson County, at an elevation 

 of 7,100 feet, where the above named birds, supposedly Transition species, breed 

 in meadows that are surrounded by lodgepole pines and spruces, the forests of 

 these trees being inhabited by true Canadian species, such as Franklin Grouse 

 and Mountain Chickadee. 



In portions of the pi-airie region the meadows dvv alkaline in character, and 

 form a somewhat different association. These areas are usually about the bor- 

 ders of alkaline ponds or in hollows in the prairies, where temporary ponds are 

 liable to occur in wet weather. The grasses are sliorter and coarser than in the 



