146 



TREES OF NORTH AMERICA 



slender glabrous branchlets marked with occasional pale lenticels, light yellow, becoming 

 light or dark red-brown and lustrous, and paler orange-brown in their second year. Win- 

 ter-buds narrowly ovoid, long-pointed, more or less falcate, bright red-brown, lustrous, 

 j' long. Bark |'-f thick, dark brown or nearly black, and deeply divided by narrow 

 fissures into broad flat ridges separating on the surface into closely appressed scales. 



Fig. 139 



Distribution. Banks of streams in the canons of the mountains of central and southern 

 Arizona (Sicamore Canon near Flagstaff and Sabino Canon, Santa Catalina Mountains); 

 and southwestern New Mexico (canon, Saint Louis Mountains, Grant County); in Chi- 

 huahua, Sonora and Lower California. 



The typical S. Bonplandiana H. B. K. with broader and more coarsely serrate leaves, 

 and flower-aments appearing from July to January from the axils of mature leaves is 

 widely distributed in Mexico and ranges to Guatemala. 



6. Salix laevigata Bebb. Red Willow. 



Leaves obovate, narrowed and rounded or acute and mucronate at apex, cuneate at base, 

 with slightly revolute obscurely serrate margins, on sterile branches lanceolate or oblong- 



Fig. 140 



