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INSECT CONTROL ON YOUNG APPLE TREES 



Round-headed Apple Tree Borer, Green Apple Aphid and Buffalo Treehopper 

 are the insects most likely to damage young apple trees in Massachusetts, 

 Occasionally the white Apple leaf hopper, San Jose Scale, European Red Mite and 

 several leaf-chewing insects such as Bud Moth, Tent Caterpillar and Gypsy 

 Moth cause some injury. 



In applying insect control measures to young trees, materials that favor 

 increases in some pest species, such as mites, should be avoided in so far as 

 possible. 



Apple Tree Borer ; The adults of this insect are beetles about three- 

 quarters inch long and with prominent white stripes on a grayish-brown background. 

 Beetles emerge frcxn their tunnels in tree trunks during late May and June and do 

 some feeding on foliage. Eggs are laid in the bark near the ground from late 

 June until late August. After hatching, three seasons are required for full 

 development of the larva or borer. Trees are greatly weakened or killed out 

 right by the larval feeding. 



The most practicable control is spraying the entire young tree and ground 

 cover close around it in late May and through June to kill the adults. Such 

 applications might correspond to the First and Third Cover sprays in the bearing 

 orchard. In severe infestations, additional applications corresponding to the 

 Second and Fourth Cover sprays would be advisable. 



Lead arsenate is effective in such a program and would do little harm to 

 beneficial species while controlling some leaf chewers in addition to the borer. 

 Lead arsenate would have no effect upon leaf hoppers, treehopper s or aphids. 



Green Apple Aphid ; This is the most abundant of the summer aphids or plant 

 lice on apple. Large numbers of wingless and migratory, winged forms are produced 

 in some 15 generations from early spring until frost. Leaves on terminals become 

 greatly distorted and in severe infestations the new twig growth may become twisted 

 and the tree misshapen. 



Parasites and predators may be enough to check the green aphid on young, 

 unsprayed trees during some seasons. In years favorable to the aphid, natural 

 controls will not be adequate, damage will result and the young trees will act as 

 a serious source of reinfestation for the bearing orchard. 



Systemic phosphates such as demeton and Phosdrin must be handled carefully 

 but will give excellent control of the green aphid (and mites) with minimum harm 

 to beneficial forms. 



Malathion is the easiest to handle of the phosphates but often gives poor 

 control unless treatments are very thorough and repeated at frequent intervals. 



TEPP, Diazinon and Trithion are other organic phosphates which might be used. 

 TEPP must be handled carefully and must be repeated, but is easy on beneficial 



