122 THE HOP, 



long to the family Cynipidae, most of the species of 

 which are gall makers and plant feeders. Several of 

 these insects are shown in accompanying figures. They 

 need no detailed practical consideration, however, ex- 

 cept that it should be pointed out that where any of 

 these insects are very abundant, and the fact can read- 

 ily be ascertained by a little close observation, remedial 

 work may not be necessary. When any considerable 

 proportion of the lice are found to be brown and swol- 

 len and nearly double the usual size, it is a sure indica- 

 tion that they contain Aphidiine parasites and that the 

 little flies which will issue from these lice will be so 

 abundant as to kill ofif the survivors without the neces- 

 sity of remedial work. So, too, when ladybird beetles 

 are very abundant upon the vines, it is safe to conclude 

 that spraying with insecticide washes will not be 

 necessary. 



Remedies — Tf the writer were a grower of hops, 

 and had suffered from the attacks of this insect, his first 

 step would be to locate every plum tree within a dis- 

 tance of half a mile from the hop yard. He would then, 

 by hook, or by crook, secure the destruction of as 

 many of these trees as possible, with the exception 

 that he would leave two or three trees of moderate 

 size among those nearest to the yard. These trees he 

 would use as traps for the hop lice and every spring, 

 along toward the end of May, he would carefully ex- 

 amine the twigs, and, if lice were at all abundant, he 

 would spray them thoroughly with a dilute kerosene 

 soap emulsion, or with a resin wash. It is reasonably 

 safe to say that if this course were or could be adopted 

 by every grower of hops, comparative immunity of the 

 crop from the attacks of these insects would be the 

 result. There will be many cases, however, where there 

 are so many plum trees near the hop field that such a 

 course would be impossible on account of the value of 

 the plum crop. This is apt to be the case especially in 



