38 AN AMERICAN FARMER IN ENGLAND. 



strength and soundness. The disease known as the yellows, 

 in peach-trees, seems to be of this nature. 



There are many facts unfavourable to both these theories, 

 and many phenomena which neither of them, in my opinion, 

 satisfactorily explain. The popular judgment in England 

 seemed to have accepted Knight s hypothesis. But while 

 every body was mourning over the degeneracy of old favour 

 ites, the utter neglect or miserable mismanagement of their 

 orchards seemed to me to bear strong testimony to the cor 

 rectness of the contrary theory. 



The practical deduction, it may be remarked, from either 

 view, does not greatly differ. By judicious management, the 

 health, vigour, and profit of a fruit-tree, which would other 

 wise, after a certain time, pine away and die, may be greatly 

 extended, if not made permanent; and trees which are already 

 failing from decrepitude or disease, may be restored. On the 

 other hand, if trees are planted in unhealthy positions, insuffi 

 ciently supplied with those materials that are necessary to the 

 formation of strong, compact wood ; if they are cruelly muti 

 lated, crowded too close together, &c., they will not only be 

 feeble and unproductive, but will be particularly liable to the 

 attacks of vermin, disease, and parasites, and, in their weak 

 condition, will soon yield their life to theso enemies. More 

 over, the insects which are bred in them will extend their 

 ravages to surrounding trees, the seeds from their parasites 

 will be scattered over the neighbourhood, and the disease 

 which is generated in them may be indefinitely extended 

 among their species. 



The most common causes of disease, decay, and decline 

 of a fruit-tree, which it is in the power of the orchardist, in a 

 great degree, to control, are these : the exhaustion from the 

 soil of those materials which are its necessary food ; the at 

 tacks of vermin, and the growth of moss or parasites ; the 



