INDEX 
Page. 
Adalia bipunctata, enemy of hop aphis 23 
Anthocoris sp., enemy of hop aphis 23 
Ants, relation to hop aphis 19 
Aphides on shrubs and trees near hopyards mistaken for hop aphis 21 
Aphis, hop, bibliography of more important writings 38-39 
control axioms 23 
measures 23-37 
on prune 31 
recommendations, summary 37 
damage, nature 21-22 
deposition of young 14-15 
early history 9 
economic importance 9-10 
effect, general, upon hops 21-22 
of heat thereon 20-21 
eggs, winter 17-18 
emergence from hibernation 12 
enemies, natural 22-23 
favorable and unfavorable conditions therefor 20-21 
field observations, importance in control work 31 
operations in control 32-35 
first appearance in season 20 
food plants 21 
generations, number on host 13 
growth, rate 15-16 
habitation 19 
habits 19-20 
head compared with that of melon aphis 15 
hibernation 10 
emergence therefrom 12 
insecticides used in control 23 
life history 10-19 
losses due to its work 10 
migrants, fall 17 
summer, theory regarding them 18-19 
migratory activities 13-14 
migrating forms 13 
necessity for thorough work in control 24 
number of spray applications used in control 24 
young deposited by viviparous females. 16-17 
on hop roots 10-12 
procrastination in control work, results 24 
protection 19 
relation of ants thereto 19 
41 
