KEY TO THE TYPICAL TREE SPECIES OF WILLOWS 



1. Stamens 3 to 12; filaments free; flower bracts deciduous. 

 2. Leaves green below; petioles eglandular at base. 



3. Capsule hairy; twigs yellow-gray; Southwest 



S. gooddingi Ball. Goodding Willow 



3. Cap. glabrous; twigs red S. nigra Marsh., Black Willow, p. 133. 

 2. Leaves pale or bluish below; ovary and capsules glabrous. 



4. Petioles without glands at base of lead. 



5. Twigs easily separable; flower bracts entire. 



6. Leaves 4-5 inches long, narrowly lanceolate to lanceolate; 



petioles under }4 inch; Southeast 



S. caroliniana Michx., Coastal Plain Willow 



6. Leaves 2^-4 inches long, lanceolate to ovate-lanceolate; 



petioles M-M inch long; northern and central 



S. amygdaloides And., Peachleaf Willow, p. 133. 



5. Twigs firmly attached; flower bracts toothed; southwest. 



7. Leaves silver-wliite below; capsules short-stalked; stamens 

 usually 3 . .S. bonplandiana H. B. K., Bonpland Willow 



7. Leaves glaucous or yellow-hairy below; capsules long- 

 stalked; stamens 4-6; Southwest 



S. laevigata Bebb, Red Willow 



4. Petioles glandular; twigs separable; flower bracts toothed; 



throughout west S. lasiandra Benth, Pacific Willow 



1. Stamens 2. 



8. Widely planted and naturalized ornamentals; capsules glabrous. 

 9. Tree with distinctive "weeping" habit; leaves glabrous; capsules 



sessile 5. babylonica L., Weeping Willow 



9. Branches not drooping; capsule short-stalked. 



10. Leaves with silky hairs on both sides; twigs green to bright 



yellow 5. alba L., White Willow 



10. Leaves nearly glabrous; twigs brownish 



S. fragilis L., Crack Willow 



8. Native species which are often shrubby and seldom planted. 



11. Bracts deciduous, yellowish; filaments free, more or less hairy; 

 stipe of ovary much shorter than bract. 



12. Leaves M-1 M inches long, linear; stigmas linear; south- 

 western S. taxi folia H. B. K., Yewleaf Willow 



12. Leaves over l}4 inches long, mostly linear-lanceolate; 

 stigmas short. 



13. Leaves white-hairy below; stipules minute or want- 

 ing; throughout west S. exigua Nutt., Coyote Willow 

 13. Leaves nearly glabrous below; stipules large, decidu- 

 ous; throughout North America 



5. interior Rowlee, Sandbar Willow 



11. Bracts persistent, darker; filaments glabrous. 



14. Ovary and capsule glabrous; bracts dark brown. 



15. Leaves acute or rounded, thin; filaments united at 



base; western. . . .S. lasiolepis Benth., Arroyo Willow 



15. Leaves acuminate, thick and leathery; filaments free. 



16. Leaves 1 M-2 inches long, oblanceolate; twigs 



glabrous; western 



S. mackenzieana Barr., Mackenzie Willow 



16. Leaves 4-6 inches long, narrow-lanceolate; twigs 



hairy; central United States 



. .5. eriocephaia Michx., Missouri River Willow 

 14. Ovary and capsule hairy. 



17. Stipe of ovary longer than light, hairy flower bracts; 



through North America 



S. bebbiana Sarg., Bebb Willow 



17. Stipe shorter than brown, hairy flower bracts; western 

 S. scouleriana Barr., Scouler Willow 



[131] 



