INSECT BLIGHT. 823 



scarcely one-tenth of an inch long ; and it escapes from the 

 branch almost as soon as, by the withering of the leaves, we 

 are aware of its attack ; hence, it is so rarely seen by careless 

 observers. In the perfect state, it is a very small beetle, deep 

 brown, with legs of a paler colour. Its thorax is short, convex, 

 rough in front, and studded with erect bristles. The wing 

 covers are marked with rows of punctured points, between which 

 are also rows of bristles, and they appear cut off very obliquely 

 behind. 



This insect deposits its egg some time in July or August, either 

 behind, or below a bud. Whether the egg hatches at once, we 

 are not aware, but the following spring, the small grub or larva 

 grows through the sap wood or tender alburnum, beginning at the 

 root of the bud, and burrows towards the centre of the stem. 

 Around this centre or pith, it forms a circular passage, some- 

 times devouring it altogether. By thus perforating, sawing off, 

 or girdling, internally, a considerable portion of the vessels which 

 convey the ascending sap, at the very period when the rapid 

 growth of the leaves calls for the largest supply of fluid from the 

 roots, the growth and the vitality of the branch are checked, and 

 finally extinguished. The larva about this time, completes 

 both its transformation, and its passage out, and, in the beetle 

 form, emerges, with wings, into the air, to seek out new positions 

 for laying its eggs and continuing its species. The small pas- 

 sage where it makes its exit, may now more easily be disco- 

 vered, below or by the side of the bud, resembling a hole bored 

 with a needle or pin. 



It is well to remark here, that the attack of this blight insect 

 is not confined to the pear, but in some parts of the country we 

 have observed it preying upon the apple and the quince in the 

 same manner. In the latter tree, the shoots that were girdled, 

 were shorter, and at the extremities of the branches only ; not 

 leading, therefore, to such serious consequences as in the pear. 



The ravages of the insect Might, we are inclined to think, do 

 not extend much below the point where the insect has deposited 

 its egg, a material point of difference from the frozen-sap blight 

 which often poisons the system of the whole tree, if allowed to 

 remain, or if, originally, very extensive. 



The remedy for the insect Wight is very distinct. It is that 

 originally suggested by Mr. Lowell, which we and many others 

 have pursued with entire success, when the other form of the 

 disease was not also present. This remedy consists, at the very 

 Jirst indications of the existence of the enemy, in cutting off and 

 burning the diseased branch, a foot below the lowest mark of dis- 

 coloration. The insect is usually to be found at the bottom of 

 this blackened point, and it is very important that the branches be 

 removed early, as the Scolytus is now about emerging from his 

 burrow, and will speedily escape us, to multiply his mischief 



