SALICACE^E 



165 



ing before the fruit ripens 4' or 5' long , their scales light brown, thin and scarious, 

 dilated and irregularly cut at the apex into filiform lobes; disk of the stain mate 



f '<< 133 



flower broad, oblique, slightly thickened on the entire revolute margins; stamens 60 

 or more, with large dark red anthers; disk of the pistillate flower cup-shaped; 

 ovary ovate or ovate-oblong, with 3 broad irregularly crenately lobed stigmas. 

 Fruit ovate, acute or obtuse, slightly pitted, thick- walled, 3 or rarely 4-valved, 

 '-' long, its stalk stout, from ytf'-J' long; seeds ovate, acute, light brown, and 

 nearly ' long. 



A tree, occasionally 100 high, with a short trunk 5-6 in diameter, and stout 

 spreading branches pendulous at the ends and forming a broad rather open graceful 

 head, and slender terete branchlets light green and covered at first with short pale 

 caducous pubescence, becoming light yellow before winter, dark or light gray more 

 or less tinged with yellow in their second year, and only slightly roughened by the 

 small 3-lobed leaf-scars. Winter-buds ovate, acute, with light green lustrous scales, 

 the terminal usually about ^' long and usually two or three times as large as the 

 lateral buds. Bark on young stems light gray-brown, thin, smooth or slightly 

 fissured, becoming on old trees l^'-2' thick, dark brown slightly tinged with red, and 

 deeply and irregularly divided into broad connected rounded ridges covered with 

 small closely appressed scales. Wood light brown, with thin nearly white sapwood. 



Distribution. Banks of streams ; valley of the upper Sacramento River south- 

 ward through western California to Lower California and eastward to central Ne- 

 vada, southern Utah, southern Colorado, and western Texas. 



Often planted in southern California as a shade-tree, and for the fuel produced 

 quickly and abundantly from pollarded trees. 



11. Populus Wislizeni, Sarg. Cottonwood. 



Leaves broadly deltoid, abruptly short-pointed, truncate or sometimes cordate at 

 the broad entire base, coarsely and irregularly crenately serrate except toward the 

 entire apex, coriaceous, glabrous, yellow-green and lustrous, 2'-2' long, usually about 

 3' wide, with slender yellow midribs, thin remote primary veins and conspicuous 

 reticulate veinlets; their petioles slender, glabrous, l^'-2' long. Flowers: aments 

 2'-4' long, the pistillate becoming 4'-5' long before the fruit ripens, their scales 

 scarious, light red, divided at the apex into elongated filiform lobes; disk of the 



