THE GENERAL PLAN OR THEORY OF THE PLACE 43 



men trees than to using in composition, — that is, as parts of 

 general groups of trees, where their characters serve to break 

 the monotony of heavier forms and heavier fohage. The 

 poplars are gay trees, as a rule, especially those, like the aspens, 

 that have a trembling foliage. Their leaves are bright and 

 the tree-tops are thin. The common aspen or ''popple," 

 Populus tremuloides, of our woods, is a meritorious little tree 

 for certain effects. Its 

 dangling catkins (Fig. 

 33), light, dancing fo- 

 liage, and silver-gray 

 limbs, are always 

 cheering, and its au- 

 tumn color is one of the 

 purest golden-yellows 

 of our landscape. It 

 is good to see a tree 

 of it standing out in 

 front of a group of 

 maples or evergreens. 



Plant-forms. 



Before one attains 

 to great sensitiveness 

 in the appreciation of gardens, he learns to distinguish plants by 

 their forms. This is particularly true for trees and shrubs. Each 

 species has its own ''expression," which is determined by the 

 size that is natural to it, mode of branching, form of top, twig 

 characters, bark characters, foliage characters, and to some extent 

 its flower and fruit characters. It is a useful practice for one 

 to train his eye by learning the difference in expression of the 

 trees of different varieties of cherries or pears or apples or other 

 fruits, if he has access to a plantation of them. The differences 

 in cherries and pears are very marked (Figs. 34-36). He may 



34. Plant-form in cherries. — Reine Hortense. 



