Bui. 1107. U. S. Dept. ot Agriculture. 



Plate V. 



Fig. 1.— Sheet of lead alloy which wa? tacked 

 over infested section of oak. Area between 

 the lines marked A was covered with a strip 

 of zinc which prevented the beetles from 

 emerging. (Table 1, No. 26b.) Photograph 

 bv H.E.Burke. 



Fig. 2.— Sheet of lead alloy just under the pre- 

 ceding. Shows how the beetles mined to the 

 side when thev were stopped bv the zinc. 

 (Table 1, No. 26b.) Photograph by H. E. 

 Burke 



< 



Fig. 3. —A . sheet of lead alloy 

 which was covered by the 

 sheet of zinc.. B. Mo"st of 

 the beetles were unable to 

 penetrate the zinc and 

 stopped in A . One, marked 

 A on sheet B, did penetrate 

 the zinc. ( Table 1. No. 2.3b. 

 Photograph bv H . E . Burke . 



Fig. 4.— Sheets of lead alloys tacked over infested wood. 

 I was covered with a sheet of lead carborundum coated 

 on the upper or outer side. It did not seem to stop the 

 beetles at all. Note clean-cut holes. 77 was covered 

 with a sheet of lead carborundum coated on the inner 

 side next to it. It seemed to stop most of the beetles. 

 Note how thev mined to the side in attempting to escape 

 boring through it. (Table 1, Nos.2a. 2b.) Photograph 

 bv H.E.Burke. 



THE LEAD-CABLE BORER. 



