INSECTS INJURIOUS TO POTATOES AND TOMATOES 273 



of damage when they are at all numerous. In addition to the 

 direct injury the aphids do they create conditions favorable for 

 fungus attack, the wounds made by their beaks serving as points 

 of infection and the weakened condition of the plants making 

 them less resistant. 



This species has been reported from Maine and California 

 and in many intermediate localities. 



Control. Dr. Patch, (1. c.), states that since the insect winters 



FIG. 234. The potato aphid. Winged summer form. (After Webster, Iowa 



Agr. Expt. Sta.) 



in the egg stage on many plants near potato fields, clean culture 

 arid destruction of weeds in the fall should be a valuable means 

 of control. She recommends, also, spraying rose bushes showing 

 infestation in the spring with tobacco extract and later, if necessary 

 spraying the potatoes with the same material. 



The Apple Leafhopper 



The apple leafhopper is so named from the fact that it is found 

 on apples, especially on young trees in the nursery. To these 

 it is quite seriously injurious, being often the most important 

 insect pest found in apple nurseries. It is called also the potato 

 leafhopper because it attacks potatoes and is even more injurious 

 to them than it is to the apple. 



* Empoasca mali LeBaron. Family Jassidce. See Bulletins 111 and 155, 

 Iowa Expt. Sta., E. D. Ball, Journal of Econ. Ent., Vol. 12, No. 2, 1919, 

 pp. 149-154. 



