SALICACE.E 



135 



acute, with light orange-brown puberulous scales. Bark pale, thick, divided by deep fissures 

 into broad rounded ridges broken into closely appressed scales. 



Fig. 129 



Distribution. The common Cottonwood along the streams in the eastern foothill region 

 of the Rocky Mountains from Saskatchewan to New Mexico, and ranging east to the Da- 

 kotas, western Nebraska, Kansas, Oklahoma and Texas. 



Often planted as a shade and street tree in the Rocky Mountain states; hardy in Mas- 

 sachusetts. 



14. Populus balsamifera L. Cottonwood. 



Populus angulata Michx. f. 



Leaves ovate, longer than broad, abruptly* acuminate and often long-pointed at apex, 

 subcordate or rarely truncate at the wide base, finely crenately serrate with glandular 

 teeth, furnished on the upper surface at the insertion of the petiole with two glands, thick, 

 glabrous, green and lustrous on the upper surface, paler below, 5'-7' long and 4 '-5' wide, 

 with stout midribs and conspicuous primary veins sometimes sparingly pilose below early 

 in the season; petioles much compressed laterally, often more or less tinged with red, 3'-4' 

 in length. Flowers: aments glabrous, short-stalked, the staminate densely flowered, 

 H'-2' long, $'-' in diameter, the pistillate slender, sparsely flowered, 3'-3' in length; 

 scales scarious, light brown, glabrous, dilated and irregularly divided at apex into filiform 

 lobes; disk of the staminate flower broad, oblique, slightly thickened and revoliite on 

 the margins; stamens 60 or more, with short filaments and large dark red anthers; disk 

 of the pistillate flower broad, slightly crenate, inclosing about \' of the ovoid obtusely 

 pointed ovary, with 3 or 4 sessile dilated lacinately lobed stigmas. Fruit on aments 8 '-12' in 

 length, ellipsoidal, pointed, thin-walled, 3 or 4-valved, \' long, the disk little enlarged; 

 pedicels jy'-|' in length; seeds oblong-obovoid, rounded at apex, light brown, about 

 T2 r long. 



A large tree with massive spreading branches and stout yellow-brown often angular 

 branchlets. Winter-buds resinous, acute, \' long with light chestnut brown lustrous 

 scales. 



