IMPORTANT PECAX INSECTS AND THEIR CONTROL. 



41 



THE RED-SHOULDERED SHOT-HOLE BORER.i 







The red-shouldered shot-hole borer infests dead or dying pecan 

 limbs, into which it bores for a considerable depth. The borings or 

 frass of the larvae are very fine and sawdust-like in appearance, and 

 arc firmly packed or compressed within the galleries, which run with 

 the grain of the wood. Upon attaining full growth the larvae pupate 

 some time during the fall or spring, and the beetles emerge during 

 the spring months. Beetles are sometimes found during the early 

 winter in the larval galleries, in which they remain until warm 

 weather begins. The beetles invariably make their way out at right 

 angles to the larval galleries, 

 and emerge through circular 

 holes in the bark, as is shown 

 in figure 48. 



According to Mr. C. A. Reed, 

 Nut Culturist in the Bureau of 

 Plant Industry, trees so se- 

 verely cut back for topworkiiig 

 or other purposes that the trunk 

 becomes saturated with sap 

 and the sap cells ruptured are 

 fairly certain to become in- 

 fested with shot-hole borers. It 

 has been observed by 'some that 

 not infrequently the borers are 

 charged with being responsible 

 for the unhealthy and appar- 

 ently diseased condition of the 

 tree, whereas actually the diseased condition of the trunk is respon- 

 sible for the presence of the insects. 



The beetle is black and has small punctures over the greater part 

 of its body. The whig covers at the base or shoulder are reddish 

 and at the tip or posterior end they are obliquely cut off, the edge 

 of the cut being armed with three conspicuous teeth. 





FIG. 48. The red-shouldered shot-hole borer ([Sinoxy- 

 lori] Xylobiops basilaris): Exit holes of adult beetles 

 in pecan limb. 



CONTROL MEASURES. 



Since the insect attacks, as a rule, only dead or dying pecan wood, 

 it is not to be considered a serious pest. Occasionally it attacks 

 rather healthy trees, but it never causes any serious damage to them, 

 since the larvae can not subsist on wood containing a good flow of 

 sap. As a protection against this insect, as well as against the more 

 injurious wood-boring species, all dead trees and prunings should 

 be removed from the orchard promptly and burned. Moreover, the 

 trees should be kept in vigorous growing condition by practicing 

 good orchard management. 



i (Sinoiylon) Xylobiops basilaris Say. 



