PEEFACE 



So niufli Las been wi'itten pi>piilai-h' and in a seientific way on 

 trees that no Ixiok on the subject woub.l )_>e warranted uidess it 

 •was designed to meet a decided need. At present there is no 

 general "work npon American trees wliich comlnnes illustrations 

 of the indi\'i(hial forms with keys for their identitication based 

 upon winter characters. Tlie forester and lumliennan. however, 

 are more caUed upon to distinguish trees in winter when leaves 

 and flowers are fallen than in summer. 1'rees, as tlie most con- 

 spicuous elements in tlie winter landscape, must also appeal to the 

 student of out door life. The interest shown liy cbisses of school 

 teachers in the Summer School in identifying specimens of twigs 

 collected the pre\"ious winter indicated that the winter study of 

 trees can be talcen up \\'itli enthusiasm by teachers in tlieir schools. 

 In our experience, the winter identification of trees has proven to 

 students one of the most interesting su1)jects of their course. It is 

 of decided value for its training in the power of accurate o))ser- 

 vation. The work comes at a time wlien material for natural 

 historv studv seems scantv and might therefoi-e 1)e "used to Jiridge 

 over tlie period lietwecji fall and spring wliich are unfortunately 

 considered liy many tlie only seasons when study of out door life 

 is possible in the scliools. A tree in winter is far from being 

 the cliaractei'less object many belie\'e. Fi't't'd fi-om its covering 

 of leaves, the skeleton of the tree is re\-ealed and wilii the metliod 

 of jjranching thus cleai'ly discei-nilde, the species may generally 

 be more readily identified at a distance than in its sununer garb. 

 Tliei'e are many forjiis, m<ireo\'i'i', that are difficult to distinguish 

 from summer features alone but which in H'inter ba\e twig, bud 

 or other chaiacters whicli make their se])aration comparatively 

 easy. It is believed that the combination of keys, iext, and illus- 

 trations from ])hotograpbs will Furnish ibe assistance whit'b the 

 current texts fail to supply and i-ender the identilicution of (Uir 

 common trees in winter a relati\ely simple task. 



The text -with keys is an oidgrowth of outlines tliat one of the 

 authors has de\'eloped and used with \'ai-ious modifications for 

 the last four \-eai-s in his college classes in ISotany and Forestry. 



