194 CAUSE OF DISEASE AMONG 



in different parts of the country. Such a weak 

 argument as this is scarcely worthy of being con- 

 futed ; for we may as well say that the plane tree, 

 which is not a native of Scotland, ought to be fast 

 degenerating also, which we know is by no means 

 the case. Another argument against this assertion 

 is, that in many places we find healthy larch 

 plantations, and in other places unhealthy, both, 

 nevertheless, being of the same age. Now, I would 

 ask such as hold the above opinion, if the larch be 

 degenerating, why is it found to succeed well in one 

 place and not in another, — and that, too, even 

 within the bounds of the same gentleman's pro- 

 perty ? The only reasonable answer that they can 

 give to this question is, that, wherever the larch is 

 found thriving well, it must be growing in a state 

 of soil agreeable to its constitution ; and wherever it 

 is found not thriving, it must be growing in a state of 

 soil not agreeable to its constitution. Therefore, 

 in our further inquiries after the cause of the rot 

 in the larch,.we must first ascertain the nature of the 

 circumstances which affect the tree in both cases. 



The larch is a native of the south of Europe, 

 and also of Siberia. It inhabits the slopes of moun- 

 tainous districts, in the lower parts of which it 

 attains its largest dimensions. In its native moun- 

 tains, the larch is never found prospering in any 

 situation where water can lodge in the ground in a 

 stagnant state ; nor is it ever found of large dimen- 



