The Trees of Wyoming. 91 



5. COTTONWOOD. 



(Poplllus) 



" He that plants trees loves others beside himself." 



The Cottonwoods need no description as a group. 

 They are known to everyone, but it may not be perfectly 

 clear that the Aspen and the Balm of Gilead are Cotton- 

 woods. In fact we shall not call them by that "common 

 name," but they as well as the other three belong in the 

 genus Populus. Our five species are easily known in the 

 summer time by the shapes of the leaves, as shown in the 

 figures accompanying the short descriptions below. Since 

 these are the trees that we must use to a large extent for 

 shade and ornamental planting"* in this state, it is desira- 

 ble that we be able to recognize them in their winter con- 

 dition also. Transplanting can most safely be done in 

 the spring before the buds open. To assist in recogniz- 

 ing them at that time the accompanying plate, showing a 

 twig and buds of each, will be helpful, as will also a study 

 of the bark character. 



(1) NARROWLEAF COTTONWOOD. 



(Popiilus angustifoha James) 



Description. Leaves small, oblong 

 or lance-shaped, usually acute at the 

 apex and with rounded base, finely scal- 

 loped on the margins: buds small, 

 pointed, dark brown (see Plate XX, 

 Fig. 5): bark thick, coarsely furrowed 

 and dark colored, these characters more pronounced as the tree grows older. 



The most abundant of the Cottonwoods (excepting 

 the Aspen) in this state. It becomes in some localities a 

 large tree, sometimes 75 feet high and 3 feet in diameter, 

 though usually it is much smaller. It occurs at intervals 

 on all the larger streams in the state either as a fringe on 



*See Bull. 38 of this Station. 



