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A BUD AND TWIG KEY. 



The -Key was first published in 1911 in the Nebraska Forest 

 Club Annual, and reprints were made and used in the class room 

 in Forest Botany. That edition is exhausted and there seems 

 still to be a demand sufficient!}'' large to warrant a revised edition. 

 In the revision however only a few species have been added and 

 a few changes made in the context. 



About 85 species of broadleaf deciduous trees are included 

 in the Key, among them are the most important forest trees and 

 a few of the more common exotics, also a few of the small trees 

 that occur on the border line between trees and shrubs. The Key 

 was worked out originally for use in a course in Forest Botany 

 and in order to give the student a hint of the broadleaf trees in 

 other than the Hardwood Region of the eastern United States, 

 a few of the western and several of the southern species were 

 included. 



In most cases the descriptions have been carefully checked 

 up with live material and are considered fairly accurate ; a few 

 however were made from dried specimens ; and some were taken 

 from the literature and not verified owing to a lack of material. 



The key is based upon features that are visible either to the 

 naked eye or with the aid of a hand-lens. The larger divisions 

 are based upon those characteristics which first attract the eye; 

 and the subdivisions, upon less and less prominent features, until 

 in the final divisions the distinctions are, in a few instances, often 

 variable to the extent of becoming more or less unreliable. The 

 uncertainty introduced here is not of any great importance and 

 can be ignored in most cases. 



In a few instances the characteristics are given for the genus 

 only. For such genera as Crataegus, Salix, Cornus, Magnolia, 

 where the species are either so numerous and indefinite or occur 

 rather rarely throughout the Hardwood Region, it did not seem 

 advisable to carry the distinctions beyond those of the genus. 



