GRUBS BORING IN STALK OR STEM 



137 



Fig. 125. — Adult of the Hop-plant 

 Borer. Original. 



existence. Early in the season it bores inside the growing tips, 



causing them to turn down. It is now a slender green worm, 



marked with black dots. Soon it drops from the tips, enters the 



vine near the ground, and bores within at this point. At this stage 



it is reddish in color, dotted with 



black, and three fourths to an 



inch in length. After two or 



three weeks, it bores down and 



out, and feeds beneath the 



ground, just above the old roots, 



sometimes nearly cutting the \ane 



off. It now reaches a length 



of two inches, is thick bodied, 



whitish, and marked with fine 



brown dots. 



A pupal stage is passed in the soil. Some of the adults emerge in 

 the fall and some in the spring. 



Tips showing the work of the earlier stage should be pinched off 

 and destroyed. The grubs working in the soil may be driven deeper 

 to the old roots b}^ pulling away the dirt for a few days, later heaping 

 ashes around the vines. On the old roots they will do little damage. 



The Cabbage Curculio {Ceutorhyncus rapce Gyll.) 



A small snout beetle appears on cabbage plants early in the season, us- 

 ually wliile the plants are still in the seed bed. The beetle is one eighth 

 of an inch long and varies in color from gray to black. Its body is quite 

 broad. Eggs are laid in the stalks, and a whitish grub tunnels 

 witliin. Infested plants may droop over in their upper half, or break 

 off in transplanting. The grub is full grown in three weeks, trans- 

 forms in the soil, and the adults emerge a week later, disappearing 

 after a few days. There is one generation annually. 



Various wild plants, especially hedge mustard and wild pepper- 

 grass, are native food plants and are preferred to cabbage. Use may 

 be made of these as traps, destroying them as soon as the beetles have 

 laid their eggs in them. An appUcation of arsenate of lead or Paris 



