but v short time The leaves, however, ere pn I for ■ lonj 



period end bo ere very useful, even to the beginner, in the identificati 

 Leaves vary greatly in size, shape, color, Bize, Burfaoe ch 



teristics, genera] appearance, etc., t>ut tl I each Bpecies are fairly 



itant within certain limits for the particular Bpecies In question. 



of the great value of leaves for purj of identification I 



have included in these preliminary pages a number of outline sketches 



which may aid in the interpretation of the various leaf characteristics 



they are mentioned in the descriptions. The characteristics of hud-. 

 in so far as they are concerned with shape, may also be readily and 



od by thinking of a vertical section of the bud in terms of L< 

 outline 



The preliminary key- are for the purpose of enabling a person to 

 locate a given unknown tree more readily than would be possible over 

 the different illustrations. The key is designed to facilitate the lo 

 tion of or the "unlocking-" of information about trees by first directing 

 the student to the names of the various trees. Keys are usually ba 

 upon the most striking or contrasting similarities and differences which 

 the various trees exhibit, and are arranged so that these characteristic - 



iid out in bold, co-ordinate contract as series of two or more alt 

 natives. Such contrasts as "leaves simple" and "leaves compound" or 

 "buds smooth" and "buds hairy" will serve to illustrate the construction 

 of the key. The practical use of the keys depends upon the following 

 through with the various alternatives and subdivisions of the key, 

 one has the specimens of a tree before him, until he is able to reach 

 one of the names at the extreme right hand margin, then turn to the 



e indicated. 



Corrections or suggestions in connection with any of the data in- 

 cluded in this handbook will be thankfully received by the author. He 

 will also be pleased to receive specimens of trees and shrubs, and in 

 fact of any plants from any part of the state, and to be of all service 



ssible to the people of Nebraska in the identification of any plants 

 that they may care to send to him. Good specimens, properly pressed, 

 which may be sent in will be added to the collections of the Botanical 

 Survey of Nebraska with full credit to the collectors and localities con- 

 cerned. 



—9— 



