INSECTS AND DISEASES. 329 



established in the tree, the labor of extermination will not 

 only be increased ten-fold, but he will suffer the pain of 

 seeing some of his handsomest trees enfeebled; and, if the 

 most prompt and vigorous measures are not adopted, 

 they will die. 



The Sorer is, when fully developed, a slender, dark- 

 blue, four- winged, wasp-si laped insect. Figure 17 gives the 

 male, and fig. 18 the female perfect in- 

 sect. It does not enter the tree in this 

 shape, but about the middle of June 

 commences to deposit its eggs on the 

 tender bark of the tree, at the surface of 

 the ground, and, occasionally, through- ^ig. 17. BORER. 

 out the summer, sometimes even as late 

 as October. These eggs hatch, as the season advances, 

 into small white grubs or borers, about one inch long 

 when fully grown, and an eighth 

 of an inch in diameter. These 

 penetrate the bark, and burrow in- 

 to the sap wood, where they re- 

 main all winter. In the spring, or 

 early summer, they emerge in their 

 Fig. 18. BORER. FEMALE, perfect, winged form, and soon 

 commence depositing eggs for another generation. 



During their stay in the tree, they devour voraciously 

 the bark and sap wood, and one or two are sufficient to 

 destroy a young tree in a single season, and four or five, 

 an old one. Their inroads are very insidious, and some- 

 times the first notice the planter has of their presence is 

 the blighting of his tree, which soon withers and dies. 

 The work being done in the dark, under the bark, and the 

 gum piled around the neck of the tree, the insect is com- 

 pletely concealed, and the injury unsuspected until, like 

 an exploded mine, the bleached and withered leaves give 

 unmistakable evidence of its fatal presence. But a little 

 experience will soon enable any one to detect the borer. 

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