BULLETIN No. 217 



WOOLLY APHID OF THE APPLE.* 

 (Schisoneiira lanigcra) 



Edith M. Patch. 



White masses looking like patches of thick mold often occur 

 on apple trees, especially about pruning wounds or other scars 

 on the trunk and branches and upon water sprouts. Beneath 

 this substance are colonies of rusty colored or purplish brown 

 plantlice known as "woolly aphids" on account of the appearance 

 of white covering which is, however, really composed of waxen 

 filaments. 



The species is common in Maine on hawthorn, mountain ash. 

 and Baldwin and some other varieties of apple. 



It is one of the migratory aphids and passes part of its life 

 cycle upon the elm**, as is explained in the following treat- 

 ment. It should not however, be confounded with those woolly 

 aphids found upon aldert an:l maple*, as the woolly aphid of 

 the apple cannot live upon those trees. 



Habits and General Djscussion. 



The woolly aphid occurs upon the apple as a bark feeder 

 and is found upon branches, roots, and tender places on the 

 trunk. These insects are covered by a white flocculent waxy 

 secretion given off as fine filaments through pores in the skin 



*Papers from the Maine Agricultural Experiment Station: Ento- 

 mology No. 67. 



**There are other elm aphids belonging to this same genus which do 

 not migrate to apple. In order to avoid confusion those are treated in a 

 separate bulletin soon to be published by this Station. 



fPemphigus tessellata (acerifoUi.) 



tPeviphigus tessellata (acerifolii) and Pemphigus aceris. 



