CHAPTER I. 



HABIT. 



Distinctions between trees and shrubs Trunk and crown Transi- 

 tions between trees and shrubs Dwarfed Scots Pines described 

 by Darwin Bush Different forms assumed by woody plants 

 Prevalent form of European trees Distinctions among these 

 drooping, fastigiate, spreading and terraced, and pyramidal 

 forms Causes of these distinctions Lombardy Poplar and 

 Spruce Weeping Willow and Cedar of Lebanon Cypress, 

 Ash, and Larch Horse-chestnut, Beech, and Birch Shrubs 

 and bushes Woody creeping and climbing plants Coppiced 

 and pollard trees " Eound-headed " trees Angle at which 

 branches are given off Terms trunk, bole, limbs, branches, 

 twigs, shoots, and spray. 



NONE of my readers would find any difficulty in pointing 

 to examples of trees and of shrubs, though any one of 

 them could easily fix the attention on individual woody 

 plants not obviously included under either head. On 

 examining the matter it is clear that the typical and 

 unmistakable tree has a single principal stem, known 

 to foresters as a bole or trunk where large timber trees 

 are concerned, and that this ramifies above into a crown 

 or head of branches ; whereas the universally accepted 

 definition of a typical shrub turns on the fact that no 

 one stem can be claimed as the principal bearer of the 

 w. v. 1 



