118 



IS SECTS • 



what the deleterious qualities are, which derange 

 and destroy the healthy hark and wood of a tree ; 

 but knowing what is stated as the cause to be a fact, 

 all we can do to prevent it is, to avoid placing trees 

 in situations where they would be liable and exposed 

 to the disease ; or if our land be of that unfavourable 

 kind, endeavour to improve it by draining, or by any 

 other means that will prevent the root frona sinking 

 into the noxious subsoil. 



Insects — Are the American aphis or coccus ^ 

 otherwise called by naturalists the woolly or frothy 

 aphis. This is too well known to need further de- 

 scription. To kill those that are visible, and stop 

 their yoang from infecting the whole tree, a wash 

 must he made of soft soap and warm soft water, 

 worked together till it is of the consistence of thin 

 paint. This must be laid on the stem and branches 

 with painters' brushes of various sizes^ and pressed 

 into every chink or opening of the bark where tlie 

 insects hide and breed. The action of the brush 

 crushes the old ones to death, and the clammy nature 

 of the wash prevents all movement of either old or 

 young. One application will not be enough to ex» 

 tirpate them, because many of the young are safe 

 and lie hidden under blisters of the bark, which, un- 

 less first pared off with a knife, neither brush nor 

 wash can reach. But if this wash be applied hot^ 

 and as often as the insects appear, a tree, or any 

 number of trees, may be freed from them in time. 

 Other remedies have been suggested, as in= 

 ferior vinegar, strong soap suds^ lime water> infusions 



