THE ASPEN. 29 



Its wood is soft and light, resembling that of 

 willow, and is seldom profitably grown after forty 

 years, as it generally begins then to rot in the centre 

 of the trunk. The timber is useful for making 

 barn doors, as it does not warp, and for similar 

 purposes as that to which willow is applied. Planted 

 alone in rich moist soil, it rises with a straight trunk 

 to a considerable height in a short time, and produces 

 a large amount of timber. 



The White Poplar (P. alba). The general appear- 

 ance of this tree somewhat resembles P. canescens, 

 though not generally so vigorous, is finer, the upper 

 surface of the leaves being of a darker green, and the 

 under side of a brighter white, which, when agitated 

 by the wind, presents a very striking appearance, and 

 has a very conspicuous effect upon the margins of 

 lakes, upon islands, or in plantations designed for 

 effect. It is not believed to be a native of Britain, 

 but is generally supposed to have been brought to 

 England at an early period from Flanders. 



The most beautiful variety is that known as the 

 white Egyptian poplar, the leaves of which are the 

 darkest green above, with the most vivid white 

 beneath, though its growth is not nearly so vigorous 

 as the common variety. 



The Trembling-leaved Poplar (P. tremuld), or 

 Aspen, is a native of Britain, and is also indigenous in 

 mountainous situations throughout Europe and Asia, 

 in the Highlands of Scotland being frequently found 

 associated with the natural birch. Unlike the 

 tapering varieties, this is a beautiful round-headed 

 tree, of stately and elegant appearance, tall in pro- 

 portion to its bulk, growing very rapidly, and being 



