CHAPTEE XXIIL 



DISEASES. 



On examining the bark of the one year's shoots of the 

 larch, it is found they are completely covered or coated 

 over with epidermis, as close and perfect, indeed, as if 

 painted, varnished, or enamelled. The young larch bark 

 is the just admiration of every one, on account of its 

 beautiful shining yellowish straw colour, which on close 

 examination is found to be thoroughly protected from 

 wet and every inclemency of the weather, and it seldom 

 or never happens that the young shoots after being 

 ripened sustain any injury either from rain, cold, or 

 frost. When, however, the succeeding year's growth 

 begins, the bark of the former year's growth rapidly 

 expands, and breaks open the beautiful epidermis 

 or enamel, leaving the bark at the end of the second 

 season's growth usually only about half covered with 

 the enamel. It is the rupturing and destruction of 

 the epidermis that is the primary cause of the ulcer 

 or blister in the larch, of which we unhappily see and 

 hear so much. I have said the primary cause, but it 

 is not the only or whole cause. The wood and bark 

 of the larch have scarcely any other protection in their 



