508 



ENCYCLOPEDIA OF PRACTICAL HORTICULTURE 



becomes darker until it assumes the color 

 of the mature beetle. 



Fig. 1. Tlie Larvae of the Flat-IIeaded Apple- 

 Tree Borer iChnisobnthiis femorata Fab. i. 

 and their worli on young apple trees. 

 (Original) 



Life History 



The eggs are fastened with a cement 

 in the crevices and under the loose scales 

 of the bark, either singly or in groups. 

 After hatching the small grubs bore into 

 the sapwood upon which they feed. Young 

 trees may thus be completely girdled by 

 their wide flattened burrows. As the 

 larvae develop they work into the older 

 and firmer wood. When ready to pupate 

 they work upward to the bark, eating 

 nearly through. After pupation the 

 adults emerge early in the spring and 

 begin egg laying. The trees selected are 

 usually unhealthy or are afflicted with 

 wounds and sunburns. Upon or around 

 such affected places the eggs are laid. 

 The presence of the larvae in healthy 

 tissue may be told by the discoloration 

 of the bark and the exudation of sap 

 from the burrows. 



Distribution 



Throu.ehout the entire T'nited States. 



Food Plants 



Especially injurious to weak or wound- 

 ed trees, but occasionally attacks young 

 nursery stock. It is especially destruc- 



tive to the apple, but also attacks the 

 pear, plum and occasionally the peach 

 and raspberry. 



t'ontrol 

 Though this pest burrows in the trunks 

 and limbs of large trees it is most de- 

 structive to young trees, the bases of 

 which are often completely girdled. 

 Therefore young trees should be pro- 

 tected from sunburn and injury to pre- 

 vent attacks of the borer. A very good 

 preventive is to paint the trunks and 

 larger limbs with a solution prepared by 

 reducing soft soap to the consistency of 

 paint, by the addition of a strong solu- 

 tion of washing soda in water. This 

 should be applied early in the spring 

 (May or June) and again in the middle 

 of the summer (July or August). The 

 young burrowing larvae may be de- 

 stroyed with a knife-blade or crooked 

 wire. 



Natural Enemies 



Internal parasites play an important 

 role in the control of this pest in the 

 East. A small chalcid and two ichneu- 

 monid parasites (Bracon charus Riley 

 and Cryptus graUator Say), prey upon 

 the larvae, while woodpeckers also dig 

 out .great numbers of them. 



The work of these natural enemies is 

 responsible for its not doing more dam- 

 age. E. O. EssiG 



Fruit Tree Bark Borer 



Euzophera semifuneralis Walk. 



The larvae bore into the bark of apple 

 and plum and related trees, not entering 

 the wood. Trees are sometimes girdled 

 by them. Distributed over the United 

 States. The borers pass the winter in 

 silken cocoons beneath the bark; their 

 cocoons quite closely resemble those of 

 the codling moth. About May 1 the 

 caterpillars change to pupae and the 

 adults emerge late in May or early in 

 June. There appears to be a second 

 brood, the moths appearing the last of 

 September. 



The larvae are about one inch long and 

 are quite variable in color but for the 

 most part of a dark pink or reddish 

 color. 



