162 TREES OP THE NORTHERN UNITED STATES 



leaves, without lobes. Stipules often large, leaf -like, and 

 more or less persistent through the summer ; sometimes 

 scale-like and dropping early. The stipules are always 

 free from the leafstalk and attached to the twig at small 

 spots just below the leafstalk. Even if the stipules have 

 dropped off, the small scars remain. Flowers staminate 

 and pistillate on separate trees (dioecious), in elongated 

 catkins in early spring. Fruit consists of catkins of small 

 pods with numerous seeds having silky down at one end. 

 The seeds usually drop early. Among the Willows there 

 are so many hybrids and peculiar varieties as to render 

 their study difficult, and their classification, in some cases, 

 impossible. The following Key will probably enable the 

 student to determine most specimens. No attempt has 

 been made to include all the cultivated forms. 



* Spray decidedly weeping 



* Spray not decidedly weeping. (A.) 



A. Rather small Willows, 10 to 30 ft. high, with broad leaves, 



usually not over twice as long as wide ; cultivated. (B.) 

 B. Leaves glossy dark green on the upper side, taper-pointed. 7. 

 B. Leaves with white cottony hairs beneath 10. 



B. Leaves rough-veiny beneath 13. 



A. Rather large Willows, 12 to 80 ft. high, with the bark of the 



trunk very rough ; leaves more elongated. (0. ) 



C. Petioles of the leaves not glandular ; tree 10 to 40 ft. high. 

 CD.) 



D. Leaves green on both sides when mature 1. 



D. Leaves glaucous beneath 2. 



C. Petioles of the leaves usually glandular ; tree 50 to 80 It. 



high. (E.) 



E. Young leaves green above and glaucous beneath 3. 



E. Young leaves ashy gray or silvery white on both sides. 4-. 



A. Small trees or almost shrubs, under 18 ft. high; bark of 



trunk rather smooth. (F. ) 

 F. Leaves ovate rather than lanceolate, sometimes truncate 



or even cordate at base. (G.) 

 O. Leaves quite broad, shining on both sides. (H.) 



H. Leaves bright green ; twigs polished green 6. 



H. Leaves very dark green, strongly fragrant when 

 bruised. . . . . . : 7. 



