44 



ly eaten by caterpillars, grubs or saw-fly larvae. Some of these enemies 

 kill the trees or their parts, or seriously injure them, while others dis- 

 figure the branches by their feeding, or by unsightly webs, and rob the 

 foliage of much of its beauty without threatening the life of the trees. 



The majority of our ornamental trees are native and are subject to 

 attack from the insects of our forests, and many of the trees atid shrubs 

 which have been introduced from, other countries prove quite acceptable 

 to our native insect pests. At different times and in various ways cer- 

 tain destructive forest insects have been introduced from Europe or else- 

 where to add to our already.- long list of pests, and others may appear at 

 any time. These introduced species are sometimes more destructive with 

 us than they appear to be in their native country, owing chiefly to 

 their freedom here from natural parasites. 



Tunnels in wood produced by borers. 



In East^ern Canada we are yet free from certain destructive shade. tree 

 insects w^hich have caused much loss in the United States south of us. 

 Sooner or later some of these mav be introduced into this Province, and 

 unless promptly recognized and controlled may become firmly established. 



