INJURIOUS INSECTS. 
17 
REMEDIES. 
The experiments of last season fully convince 
me that this pest can readily be kept in check 
by the use of kerosene emulsion, but to destroy 
Fig. 8.—The Western Grape-vine Leaf-hopper, Typhlocyba vitifex 
Fitch, var. coloradoensis Gill. (Original). 
the mature hoppers, it should be made not weaker 
than one-fifteenth kerosene, and then it will not be 
wholly effectual if used in the middle of the day. 
The application should be made as early in the 
morning as one can see to work and before the sun 
is up to raise the temperature enough to make the 
hoppers active. Then, by throwing the spray upon 
the vines with a good deal of force, the hoppers 
can nearly all be knocked to the ground and de¬ 
stroyed. For further remedies see Bulletin 15 of 
this station. 
