2l6 MAINE AGRICULTURAL EXPERIMENT STATION. I915. 



1912. Davidson, W. M. Macrosiphum solanifolii. Aphid notes from 



California. Journal of Economic Entomology. Vol. 5, p. 411. 



Recorded from wild lettuce. 

 1912. Patch, Edith M. Macrosiphum solanifolii. Aphid Pests ot 



Maine. Me. Agr. Expt. Sta. Bulletin 202, p. 178. Apparently 



this species collected from Gladiolus and cultivated Iris. 

 .T913. Britton, W. E. Macrosiphum solanifolii, 12th Rept. of the State 



Entomologist of Connecticut for 1912, p. 294. Reported from 



leaves of corn and potatoes.- ■ 

 1914. Patch, Edith M. Macrosiphum solanifolii. Maine Aphids of the 



Rose Family. 'Me. Agr. Expt. Sta., Bulletin 233, p. Recorded 



from Japanese rose. 

 T915. Webster, R. L. Macrosiphum solanifolii. Potato Insects. Agr. 



Exipt. S'ta., Iowa St. Col. of Agric. and Mech. Arts. Bui. 155, 



pp. 400-406. Recorded from two species of wild ground 



cherry. (Physalis). 



NATURAL CONTROLS. 



It is always well to bear in mind concerning the injury inflicted 

 by any plantlouse that so many elements of uncertainty enter 

 into the career of these insects that it is quite impossible to 

 predict whether such a pest is likely to trouble us for two or 

 many consecutive years, or succumb to some adverse condition 

 and practically disappear for a long time. 



The weather, for instance, plays an important part in the 

 welfare of aphids, heavy rains washing the tender forms from 

 the plants, and cold days retarding the rate of their increase. 



Certain climatic conditions are favorable to fungus parasitism 

 which may sweep out the plantlice from a large area in a few 

 days' time. 



Then, too, in some seasons, predaceous and parasitic insects 

 appear in numbers sufficient to render any artificial remedial 

 measures superfluous. 



REMEDIAL MEASURES. 



Clean culture. Since the pink and green potato aphid passes 

 the winter in the egg stage presumably upon a great variety 

 of weeds near infested potato fields, the practice of fall plowing 

 commends itself, and also the burning over of weedy places in 

 the vicinity of potato fields in the fall or early spring. As it 

 seems not impossible, although it has not been observed in the 

 field, that belated individuals might under certain conditions 



