INSECTS INJURIOUS TO CONIFERS. 61 



Aphis juniper i is mentioned as infesting the various Juni- 

 per as well as a species of Thrips (Thrips juniperi.} To 

 completely destroy these little insects, it is only necessary 

 to drench them well with a solution of whale-oil soap or 

 tobacco water. Perhaps the best and most convenient 

 remedy is hot water a few degrees below the boiling point, 

 which will not injure the plant but effectually destroys 

 these pests. 



Scale-Insects, The Scale-insects are occasionally found 

 on some of the Coniferfe, and more particularly on many 

 of the Junipers. In fact, so injurious are they on some 

 specimens, even of a large size, that we have known the 

 plant to be killed in a single season. They will attack the 

 leaves of pines, particularly if the tree should be in an un- 

 healthy condition. These insects are the most formidable 

 enemies we have to contend with, owing to their peculiar 

 habits. 



The visible token by which we recognize the presence 

 of these pests is the scale-like covering ; this is in reality 

 the relics of the parents which remain to act as a protection 

 to the young brood; these extract the juices from the 

 tree beneath their tough covering, and kill it gradually. 

 As we cannot apply to the scale any of the various solu- 

 tions that are employed in killing the Plant-lice, it becomes 

 necessary to scrape them off; and here again another diffi- 

 culty arises, for among the multitude of closely imbricat- 

 ed leaves found on the Junipers, this plan is absolutely 

 impossible. The hot water remedy with us is first tried 

 thoroughly, and if that fails to remove these tough little 

 coverings, we proceed to the final resource, that recom- 

 mended by the old Dutch farmer for killing off the curcu- 



O 



lio, i. e. "Cut the trees down;" only in our case it has 

 the recommendation of preventing the insects from spread- 

 ing to other trees in the vicinity. 



The Piiie-leaf Scale-insect, (Aspidiotus pmifoUa), is 



