FOREST FLORA OF THE ROCKY MOUNTAIN REGION. 



By George B. Sud worth, 



Forestry Division. 



The following chapter is iuteudecl to embody an account of all the 

 strictly woody plants occurring in the Rocky Mountain region. These 

 have been divided into arborescent and non- arborescent species. But 

 the dividing line must necessarily be an arbitrary one, and undoubtedly 

 many exceptions could be taken to the species thus termed arborescent, 

 a large number being little more than shrubs as commonly found, yet 

 the controlling feature has been rather the capabilities of each species 

 under specially favorable conditions, such as may occur more or less in 

 the region under consideration. 



Besides the range of each species within the Rocky Mountain region, 

 the general distribution of those species not particularly confined to 

 these limits has been placed in parentheses and given mostly in general 

 terms. The descriptions of the species do not pretend to be technical 

 (or even complete), the attempt here made being rather to avoid, as far 

 as possible, the use of such botanical terms as will not be readily un- 

 derstood by the laymen, and to note such characters as are most apt to 

 be seen by the casual observer; hence the lack of attention to floral 

 organs as ptudied by the professional botanist. An artificial key to the 

 genera and species has been prepared on the same basis, and it is 

 hoped will lend some aid to the laymen in studying the flora. A fuller 

 description has been given only for the arborescent species. 



The conifers have been somewhat arbitrarily arranged and placed 

 first, as in this region at least they are without doubt forestally of 

 greatest importance; otherwise the order of arrangement followed is 

 that of Bentham and Hooker's Genera Plantarum. The nomenclature 

 is that given by Dr. Gray in his Synoptical Flora of North America, 

 supplemented by that adopted by Dr. George Englemann, Professors 

 Sereno Watson, M. S. Bebb, and 0. S. Sargent. As regards the com- 

 mon names used, such confusion exists that it is difficult to determine 

 which names are most used and most appropriate ; for in many sections 

 the same name is applied to different species. But it is highly desir- 

 able for practical purposes that a uniformity in nomenclature should be 



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