SALICACEAE 341 



1. SalLx marginkta Weimer. A spreading shrub or small tree, with reddish, rather 

 brittle twigs and glabrous or rarely permanently sparingly pubescent foliage. Leaf-blades 

 oljlong, lanceolate or ovate-lanceolate, or more rarely ovate to obovate, 2-5 cm. long, 

 mostly acute or blunt, serrulate, paler beneath than above, cuneate to truncate at the base, 

 sliort-petioled : aments appearing with the leaves, the staminate 3-6 cm. long ; bracts densely 

 pubescent : pistillate aments becoming 4-7 cm. long, rather large : capsules ovoid-conic, 

 4-5 mm. long, glabrous, nearly twice as long as the pedicel at maturity. 



On river banks and in swamps, North Carolina to Florida and Louisiana. 



2. Salix nigra Marsh. A tree, reaching a height of 40 m. , often 10-20 m. high. 

 Trunk sometimes 1 m. thick : bark flaky : twigs brittle, brown, glabrous : leaf-blades nar- 

 rowly lanceolate, 6-12 cm. long, paler beneath than above, finely serrate, acute at both 

 ends ; petioles sparsely pubescent : staminate aments 4-6 cm. long, slightly less than 1 

 cm. thick, rather closely flowered, borne on short leafy I)ranches ; bracts ovate, white, 

 finely pubescent : stamens 3-7 : filaments hairy at the base : pistillate aments 4-8 cm. 

 long, or 10-12 cm. in length and 1 cm. thick at maturity ; bracts oblong, finely pubes- 

 cent : stigmas notched : capsules 4-5 times as long as the pedicels, which are not more than 

 three times the length of the glands, borne rather closely on the rachis. 



In low grounds and along river banks, New Brunswick to Ontario, California and Florida. — A 

 variety with narrow falcate leaf-blades 4-6 mm. wide and green on both sides, ranging from Massachu- 

 setts to Florida, is S. nigra falcdta ( Pursh ) Torr. 



3. Salix amygdaloides Anders. A small tree reaching a height of 20 m., with a 

 trunk diameter of 6 dm. Bark scaly : leaf-blades broadly lanceolate, 8-12 cm. long, about 

 2 cm. wide, sharply serrulate, glabrous in age, dark green above, paler or glaucescent 

 beneath ; petioles slender, without glands, 6-15 mm. long : aments appearing with the 

 leaves, on short lateral branches, the staminate 3-5 cm. long ; bracts somewhat laubescent : 

 pistillate aments becoming 6-10 cm. long, lax : stigmas nearly sessile : capsules narrowly 

 ovoid, about as long as the slender pedicels, acute, glabrous. 



Along streams or lakes, Quebec to British Columbia, New York, Texas and New Mexico. 



4. Salix 16ng;ipes Anders. A shrub or small tree, rarely attaining a height of 10 m. 

 Eark deeply cross-checked, not flaky : twigs not brittle at the base, gray or gray-brown : 

 leaf-blades narrowly lanceolate, 10-15 cm. long, finely serrate, green above, glaucous and 

 veiny beneath, more or less pubescent when young, becoming glabrous at maturity; petioles 

 finely pubescent ; stipules spinulosely denticulate : staminate aments 4-10 cm. long, often 1 

 cm. thick ; bracts ovate, pale, finely ciliate : stamens 3-7 or rarely more ; filaments united 

 and villous at the base : pistillate aments 3-5 cm. long, during anthesis on short leafy 

 branches ; bracts white, oblong, sparsely pubescent, one-half as long as the ovary : stigmas 

 minutely notched : capsules conic, 4-6 mm. long, 3-4 times as long as their pedicels. \S. 

 TFardiBebb.] 



In rocky and gravelly stream beds and along rivers, Maryland to Missouri, Florida and Texas. 



5. Salix frdgilis L. A tall and graceful tree, becoming 25 m. high, with a maxi- 

 mum trunk diameter of 2 m., the branches more divergent than in S. alba. Bark longi- 

 tudinally furrowed but not exfoliating : twigs brittle at the base : leaf -blades lanceolate, 

 green and glabrous, more or less glaucous beneath, 10-15 cm. long, 1-3 cm. wide, irregu- 

 larly serrulate, acuminate ; petioles glandular above : staminate aments on leafy branches, 

 2-5 cm. long ; bracts oblong, obtuse, pubescent : stamens usually 2, rarely 3 or 4 ; filaments 

 free, pilose toward the base : pistillate aments becoming 7-12 cm. long, lax : capsules long- 

 conic, glabrous, on pedicels about twice as long as the glands. 



Escaped from cultivation in the eastern United states. Native of Europe. 



6. Sallx alba L. A large tree of exceedingly rapid growth, often attaining a 

 height of 20-30 m., often with a massive trunk 1-2.5 m. in diameter. Bark dark gray, longi- 

 tudinally furrowed : twigs brown, olive-green, or yellow : leaf-blades narrowly lanceolate, 

 more or less silky on both sides, pale or glaucous beneath, obscurely serrate, 5-12 cm. long, 

 1-2 cm. wide ; petioles sometimes sparingly glandular : aments appearing with the leaves : 

 stamens two ; filaments pilose below : pistillate aments 3-6 cm. long : style short and 

 thick : capsules ovoid, acute, rarely containing fertile seeds. The staminate tree is rare. 



In low grounds and moist soil, naturalized in eastern North America, except the extreme north. 

 Native of Europe and Asia.— The most common form is S. alha vitdUna (L.) Koch, with glabrous leaves 

 and twigs brilliant yellow especially in spring at which time the hue of the tree is very striking. 

 Another variety, S. alba coendea (J. E. Smith) Koch, with blue or bluish twigs, is commonly cultivated. 



7. Salix Babylonica L. A large tree, sometimes 20 m. high, with elongated grace- 

 ful pendant branches. Leaf-blades narrowly lanceolate, 8-12 cm. long, 10-19 mm. wide, ser- 

 rulate, tapering at the base, acuminate at the apex, sometimes curling ; petioles glandular 

 above : aments appearing with the leaves, about 3 cm. long ; bracts ovate-lanceolate, 



