92 INSECTS INJURIOUS TO VEGETATION. 



winding and irregular passages being in an upward direction 

 from the place of their entrance. For a time they cast their 

 chips out of their holes as fast as they are made, but after a 

 while the passage becomes clogged and the burrow more or 

 less filled with the coarse and fibrous fragments of wood, to 

 get rid of which the grubs are often obliged to open new holes 

 through the bark. The seat of their operations is known by 

 the oozing of the sap and the dropping of the sawdust from 

 the holes. The bark around the part attacked begins to swell, 

 and in a few years the trunks and limbs will become disfigured 

 and weakened by large porous tumors, caused by the efforts of 

 the trees to repau* the injuries they have suffered. According 

 to the observations of General H. A. S. Dearborn, who has 

 given an excellent account* of this insect, the grubs attain 

 their full size by the twentieth of July, soon become pupsB, 

 and are changed to beetles and leave the trees early in Sep- 

 tember. Thus the existence of this species is limited to one 

 year. 



Whitewashing, and covering the trunks of the trees with 

 grafting composition, may prevent the female from depositing 

 her eggs upon them ; but this practice cannot be carried to any 

 great extent in plantations or large nurseries of the trees. Per- 

 haps it will be useful to head down young trees to the ground, 

 with the view of destroying the grubs contained in them, as 

 well as to promote a more vigorous growth. Much evil might 

 be prevented by employing children to collect the beetles while 

 in the act of providing for the continuation of their kind. A 

 common black bottle, containing a little water, would be a 

 suitable vessel to receive the beetles as fast as they were gath- 

 ered, and should be emptied into the fire in order to destroy 

 the insects. The gathering should be begun as soon as the 

 beetles first appear, and should be continued as long as any 

 are found on the trees, and furthermore should be made a 

 general business for several years in succession. I have no 

 doubt, should this be done, that, by devoting one hour every 

 day to this object, we may, in the course of a few years, rid 

 ourselves of this destructive insect. 



* Massachusetts Agricultural Kepository and Journal, Vol. VI. p. 272. 



