46 



TREES AND SHRUBS 



2. SALIX l. Willow 



Shruba or small trees, from a few inches to several feet high; 

 leaves from narrowly linear to short elliptic or obovate; flowers in 

 amei.K appearing before or with the leaves; perianth a single scale; 

 stamens few; pistils single, with a gland at the base of the ovary, 

 the stigmas short; fruit a capsule containing numerous very small 

 hairy 51 



Leaves usually only about 3 times as long as 

 broad, elliptic oval to obovate, never nar- 

 rowly lanceolate or linear; capsule hairy 

 (except in S. Monticola). 



Styles obsolete or less than .5 mm. long. 

 Alpine plants less than 4 inches high. 

 Small trees or shrubs, at middle elevations 



in the mountains; much more than 4 



inches high. 



Amenta slender, lax: scales pale; stigmas 

 very short; leaves elliptic lanceolate. 



acute. 



Amenta stout, dense: scales dark; stig- 

 long, slender; leaves obovate, 

 obtuse or abruptly acute. 

 Styles elongated, 1 mm. long or more. 

 Leaves glabrous on both surfaces, bright 



green amenta closely si ssile. 

 Leaves pubescent, sometimes sparingly so, 

 at least on the upper surface; aments 

 on leafy stem. 



Capsules glabrous. 

 Capsules tomentose. 

 Plants 1 to 5 feet high. 

 Plants less than 4 inches high. 

 Leaves several times as long as broad, linear to 

 long-lanceolate; capsule glabrous (or weakly 

 Villous in Nos. 10, 11, 12). 



Scales not pale yellow, mostly brownish and 

 persistent. 

 Leaves broadly lanceolate: young branches 

 not glaucous; capsules distinctly pedi- 

 cellate; stipules conspicuous on young 

 branches. 



Leaves narrowly oblong-lanceolate; young 

 branches very glaucous; capsule sub- 

 sessile. 



Scales pale yellow, deciduous. 



Stamens 2, hairy below; leaves more or less 

 canescent, linear, remotely denticulate 

 or sometimes entire; capsules more or 

 less hairy. 



Capsule 3 or 4 mm. long; leaves % to 1% 



inches long, finely pubesceitf. 

 Capsule 5 to 7 mm. long, glabrate; leaves 



2 to 4 inches long. 



1. S. saximontana. 



2. S. bebbiana. 



3. S. scouleriana. 



4. S. chlorophylla. 



7. 5. monticola. 



6. S. glaucops. 



5. S. petrophila. 



8. S. cordata xcatsoniL 



9. S. irrorata. 



12. S. taxifoHa. 



