24 



UNIVERSITY OF CALIFORNIA EXPERIMENT STATION. 



The sort of apparatus which was used successfully on a badly in- 

 fested vineyard near Lodi this year was the vine-hopper cage shown in 

 figure 18. This device was constructed for capturing the vine hopper, 

 and when a nearby vineyard became infested with the beetles it was 

 used against them. 



This cage consists of .an ordinary mosquito netting tacked over a 

 square framework of laths or some other light material. The essential 

 part of it so far as the beetles are concerned is the tray at the bottom. 

 This is made of a sheet of galvanized iron turned up about an inch at 



the edges. The 

 crude oil which 

 is placed in this 

 tray is fatal to 

 all insects falling 

 into it. 



The V-shaped 

 opening in the 

 tray permits the 

 cage to be pushed 

 on to the vine, 

 which is bumped 

 at the same time 

 and the beetles 

 jarred off. A pad- 

 ding of leather 

 is tacked on the 

 base of the open- 

 ing in front of 

 the vine. The 

 opening may be 

 closed by tacking 

 two strips of can- 

 vas, one on each side, so as to meet in the center. These strips are sup- 

 ported by transverse pieces of three-quarter inch rubber tubing, which 

 are sewed on to the canvas beneath. This rubber tubing supports the 

 canvas over the opening, and when the cages are placed in position it 

 gives way for the base of the vine, but immediately springs back again 

 through the flexibility of the rubber. Steel strips will answer the same 

 purpose, but the rubber is described because it is cheaper and more 

 easily obtained. 



This cage has the advantage of catching the vine hopper, which is 

 likely to be present, with the same operation. For the beetle alone, 

 simply the tray at the bottom may be used, or the sides extended up 



FIG. 18. A cage used to capture the beetles on the vine. 



