Salix Salicaceae 355 



Ovary stalked, sometimes the stalk rather short. 



Stigmas sessile or subsessile (style, if any, less than 0.5 mm long); petioles without 

 glands. 



Leaf margins entire; leaves glaucous beneath 15. S. pedicellaris. 



Leaf margins more or less serrate. 



Margins of leaves with widely spaced, slender, sharp teeth 8. S. interior. 



Margins of leaves finely and evenly serrate. 

 Petioles of mature leaves 3-6 mm long. 



Blades green beneath 1. S. nigra. 



Blades whitish beneath 5. S. longipes var. Wardi. 



Petioles of mature leaves 6-15 mm long; blades paler beneath 



2. S. amygdaloides. 



Stigmas on distinct styles 0.5-1 mm long; petioles mostly glandular at the apex. 

 Petioles not glandular; leaves glaucous beneath. 



Leaves more than 5 mm wide 19. S. glaucophylla. 



Leaves less than 5 mm wide 16a. S. Candida var. denudata. 



Petioles glandular at the apex; leaves not glaucous beneath. 



Capsules maturing after June 20, 7-9 mm long 3. S. serissima. 



Capsules maturing before June 20, 5-8 mm long. 



Catkins sessile 18. S. cordata. 



Catkins distinctly stalked. 



Leaves of branchlet below the catkin stalk entire 7. S. fragilis. 



Leaves of branchlet below the catkin stalk serrulate. 



Catkins loosely flowered; capsules conic-subulate; pedicel twice as long 

 as the gland. (See excluded species no. 166, p. 1038.) <S. pentandra. 

 Catkins densely flowered; capsules conic-ovoid; pedicel 2-3 times as 

 long as the gland. 



Leaves glabrous on both surfaces 4. S. lucida. 



Leaves pubescent beneath 4a. S. lucida var. intonsa. 



Ovary pubescent; bracts of flowers persistent. 

 Ovaries pedicellate. 



Stigmas sessile or subsessile. 



Catkins sessile or subsessile 14. S. Bebbiana. 



Catkins on short, leafy stalks S. S. interior. 



Stigmas on short styles, usually 0.25-1 mm long. 



Catkins on short, leafy stalks 10. S. petiolaris. 



Catkins sessile or subsessile, rarely with 1-3 bracts at the base, appearing on old 

 wood mostly before the leaves. 



Bracts of flowers not darker at the apex 16. S. Candida. 



Bracts of flowers darker at the apex. 



Mature capsules 3-5 mm long, blunt 11. S. sericea. 



Mature capsules mostly 6-12 mm long. 



Branchlets of previous year glabrous or nearly so; catkins in flower 

 mostly more than 2.5 cm long, 3-8 cm long in fruit. . . .9. S. discolor. 

 Branchlets of previous year more or less densely puberulent. 



Catkins more than 2.5 cm long; leaves 5-10 cm long and 2-3.5 cm wide, 



the margins somewhat toothed 9a. S. discolor var. latifolia. 



Catkins less than 2.5 cm long, usually 1-1.5 cm long; leaves smaller, 

 more or less undulate or entire, rarely with a few teeth. 

 Shrubs mostly 6-12 dm high; mature leaves erect or spreading, 

 glabrous or glabrate above and beneath, or the midrib remaining 



pubescent 12. S. humilis. 



Shrubs mostly 4-8 dm high; mature leaves erect, pubescent above and 

 more or less tomentose beneath; petioles about 3 mm long, for 

 the most part shorter than those of the preceding. . .13. S. tristis. 

 Ovaries sessile or subsessile; catkins appearing before the leaves. 



