THE OAK PRUNEK. 7 



NATURAL ENEMIES. 



As might be inferred from its manner of life, this insect enjoys 

 as nearly perfect exemption from predaceous or parasitic attack as 

 falls to the lot of most wood borers. Fitch, however, has stated 

 that some of our insect-eating birds destroy the larvae, and the writer 

 has reared the parasite Bracon eurygaster Brulle from twigs inhabited 

 by the species. 



Among natural enemies of the oak pruner, Mr. F. H. Mosher*^ 

 records the downy woodpecker (Dryobates pubescens), the blue jay 

 (Cyanocitta cristata), and the black-capped chickadee (Penthestes 

 atricapillus). Mr. W. L. McAtee, of the Bureau of Biological Sur- 

 vey, states that a species of Elaphidion is preyed upon by the downy 

 woodpecker and by the great-crested flycatcher {MyiarcliUs crinitus). 

 Mr. A. H. Kirkland'* records having found a spider (Theridium tepi- 

 dariorum C. Koch) feeding upon the mature insects. 



REMEDIES. 



The pruning process is not always in itself especially injurious, 

 since when the pruner occurs in only moderate numbers the vitality 

 of the tree is not impaired. The ultimate effects, however, are likely 

 to be more serious. The fallen twigs serve as a breeding place for 

 hosts of other wood borers, many of which are injurious to shade 

 trees and to standing timber. Some of these do not hesitate, in 

 default of an abundance of dead or injured wood, to attack and 

 damage apparently healthy living trees. 



In-case this species becomes injuriously abundant, it may be readily 

 controlled by gathering the pruned twigs and burning them. This 

 should be done from time to time, as otherwise they accumulate and 

 make the lawn unsightly. To make this remedy of any value, the 

 cooperation of neighbors is desirable. The work should be as 

 thorough as possible. If the twigs are gathered in numbers during 

 one season, the chances are that the insects will not be nearly so 

 abundant the year following. 



Approved : 



James Wilson, 



Secretary of Agriculture. 



Washington, D. C, October I4, 1910. 



a Forty-fifth Annual Rep. Sec. Mass. State Board Agr. for 1897 (1898), p. 244. 

 [Cir. 130] 



o 



