226 



PESTS OF ORCHARD AND SMALL FRUITS 



and garden crops, and is discussed under the heading " White Grubs, " 

 in the section on Insect Pests of Garden and Field Crops, page 109. 



The Woolly Apple Aphis {Schizoneura lanigera Hausm.) 



The woolly aphis is found both on the larger twigs or limbs and on 

 the roots of apple trees. It is characterized by a white, fluffy secre- 

 tion, looking like little masses of cotton. On the twigs it is found in 



Fig. 282. 



Apple root showing characteristic work of the 

 Woolly Apple Aphis. Original. 



clusters on the more tender bark, especially at the axils of twigs or 

 where there has been some break in the bark, or on water sprouts. 

 Its work here results in a swelhng, which is apt later to crack open. 

 On the roots the attack causes knotty enlargements. The root forms 

 are the more serious, because of interfering with the normal functions 

 of the roots. Attack is especially severe on newly set trees, which are 

 less able to withstand injury. 



For the greater part of the year the lice are wingless. Toward the 

 end of summer winged individuals are developed, and these fly to 

 new hosts, where, after a succeeding sexed generation, eggs are laid 

 in crevices of the bark. Hibernation is accompHshed both by these 

 eggs and by the subterranean colonies. 



For the lice working above ground spray with tobacco extract or 

 with 7 per cent kerosene emulsion. Apply the material with con- 

 siderable force. For those beneath ground draw back the earth from 

 around the tree to a distance of 2 or 3 feet and a depth of 4 



