SALICACEAE 



The Willows 



Characteristics of the Genus Salix L. 



HABIT. Shrubs or less frequently trees; latter often with 

 several trunks from greatly extended rootstalk. 



LEAVES. Alternate; simple; commonly lanceolate; margins 

 entire or toothed; pinnately veined; sessile or short-petioled ; 

 stipules small and soon falling, except on vigorous shoots where 

 they are leaflike and persistent. 



FLOWERS. Regular; dioecious; in terminal and axillary 

 aments, appearing with or before the leaves; individual flowers 

 solitary, apetalous, on glandlike disk, subtended by pubescent, 

 entire to dentate, deciduous or presistent scale or bract; staminate 

 with 1-2 or 3-12 stamens inserted on base of bract; pistillate a 

 single, 1 -celled, sessile or stalked ovary, containing 4-8 ovules 

 on each of 2 placentas, style short, terminating in 2 short, 2- 

 parted stigmas. 



FRUIT. A 1 -celled, 2-valved, acuminate capsule. Seed: 

 small, dark brown, tufted with long, silky hairs, bouyant, of 

 transient vitality. 



TWIGS. Slender to stout; round; tough; often easily sepa- 

 rated at junction with branch; marked by elevated leaf scars; 

 pith homogeneous, terete. Winter buds; terminal absent; lateral 

 covered by single, caplike scale. 



BARK. Astringent; scaly; variously colored. 



WOOD. Light; soft; weak; usually brittle; durable in some 

 species; heartwood pale brown, often tinged with red; used 

 to small extent for athletic goods and charcoal. 



SILVICAL CHARACTERS. Intolerant; fast-growing; re- 

 markable vitality and sprouting vigorously from stumps or 

 cuttings; usually swamp or moisture-loving plants, 



GENERAL. This genus contains about 1 70 species scat- 

 tered over the Northern Hemisphere, with about 100 species 

 native to North America; identification of the various species 

 is difficult; 38 native and 4 naturalized species have been listed 

 as occasionally reaching tree size in North America, but only 15 

 of these native species are commonly trees, and included in the 

 key with the naturalized species. 



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