Trees and How to Know Them [ 355 



The Quaking Aspen: The quaking aspen's leaves are shiny green 

 above and pale dull green below; in the fall they turn golden 

 yellow some time before they are shed. In spring the quaking 

 aspen flowers appear in the form of drooping catkins a compact 

 spike of flowers from an inch and a half to two and a half inches 

 long. 



Young trees have yellowish-green or nearly white powdery bark 

 which is marked with horizontal creases and scars. On old trees 

 the bark near the base is almost black, and roughened by bands 

 of wartlike growths. For years the wood was considered quite 

 worthless. Today it has a very real value as a source of paper, 

 especially magazine stock. 



The Popular Cottonwood: Another widespread and well-known 

 poplar is the cottonwood. You are likely to encounter it on dry 

 western plains where other trees cannot gain a foothold or in a 

 large city where its shiny, leathery leaves successfully shed smoke 

 and dirt. However, many cities prohibit the planting of the cotton- 

 wood because its extensive shallow root system often breaks up 

 sidewalks and its tiny rootlets, in their quest for water, fill drain- 

 pipes. 



Cottonwoods Grow Fast: Children who are impatient for things 

 to grow up can enjoy watching cotton woods develop. These trees 

 have been observed adding four or five feet to their height in a 

 year; some have grown a hundred feet in fifteen years. This is 

 rather more than average height for a cottonwood, yet you may 

 find one growing as tall as 150 feet, given favorable conditions. 

 It develops a massive trunk that divides near the ground. 



WILLOWS GENERALLY FOUND NEAR WATER 

 Children are quickly attracted to some of the willows. One 

 introduction is all they are likely to need to the huge but ex- 

 tremely graceful willow, with its long, narrow, pointed leaves, 

 some of which droop to the ground. A boy with his first jackknife 

 loves the willow because the bark is easily removed in whole sec- 



