32 



BUDS. 



[section 4. 



the "Rose, Blackberry, and "Raspberry. That is, these shoots ave apt to 

 grow all smiiiucr lung, until stopped by the frosts of autumn or some other 

 cause. Consequently they form and ripeu no terminal bud protcetcd by 

 scales, and the upper axillary buds are produced so late in the season that 

 they have no time to mature, nor has their wood time to solidify and ripen. 

 Such stems therefore commonly die back from the top in winter, or at 

 least all their upper buds are small and feeble ; so tlie growth of the suc- 

 ceeding year takes place mainly from the lower axillary buds, which are 

 more mature. 



63. Deliquescent and Excurrent Growth. In the former case, and 

 wherever axillary buds take the lead, there is, of course, no single main 

 stem, coutiuued year after year in a direct line, but the trunk is soon lost 



in the branches. Trees so formed commonly have rounded or spreading 

 lops. Of such trees \\\i\\ di'litjuescoU stems, — that is, with the trunk 

 dissolved, as it were, into tlie successively divided brandies, — the connuon 

 Americau Ehn (Fig. 80) is a good illustration. 



64. On tlic other hand, the main stem of Firs and Spruces, unless de- 

 stroyed by some injury, is carried on in a direct line throughout the whole 

 growth of the tree, by the development year after year of a terminal bud : 

 this forms a single, uninterrupted shaft, — an excurrent trunk, which can- 

 not be confounded with the branches that proceed from it. Of such ^/j/z-y 

 or spire-shaped trees, the Firs or Spruces are characteristic and familiar 

 examples Tliere are all gradations between the two modes. 



Fxu. 8U. An American Ehu, with Spruce-trees, and on the left Arbor Vita. 



