328 AGRICULTURE OF MAINE. 



iv order that the trees may be thrifty and better able to with- 

 stand attack. Proper regard for these measures should give 

 practical exemption from injury. 



I 3. Shot-Borer. 



{Xylehorus dispar.) 



The female beetles bore into the wood, making deep channels 

 ^>hich in small twigs interfere with the circulation of the sap, 

 and the twigs wither, giving the appearance of blight. The 

 exit holes through the bark are .06 of an inch in diameter and 

 nearly circular, looking like small shot holes. The wood is 

 green, showing that the insect attacks the growing tree. Liv- 

 ing wood does not appear to be essential to the life and comfort 

 of this species, for after a period of several weeks we found 

 in a limb that had been in a dry place in a box, young larvae, 

 full grown pupae, and perfect beetles. 



When the larvae are full grown they transform to pupae in 

 the burrows, and finally emerge as small beetles about one-tenth 

 of an inch long and of a dark brown or nearly black color, with 

 the antennae and legs of a rusty red. The thorax is short, very 

 convex, rounded and roughened. The wing covers are marked 

 by longitudinal rows of punctures. The hind part of the body 

 slopes abruptly. The beetles leave their burrows in June and 

 July and deposit eggs before August. 



REMEDIES. 



As the beetles work wholly under the bark they cannot be 

 reached by insecticides. The only way is to watch the trees 

 during the latter part of June and July and, if blighted twigs 

 or diseased limbs are noticed, examine the branches for small 

 pin holes; if found, the presence of this or some related species 

 may be suspected. The diseased limb should at once be cut 

 far enough below the injury to include all the burrows, and 

 burned, to prevent the beetles emerging and attacking new trees. 

 As these beetles live in forest trees, orchards near timber are 

 more liable to become infested. 



