50 



In 1896 Mr. J. G. Jack published in Garden and Forest (July 1, 1896, 

 p. 269) a short account of injury to birch trees in the Arnold Arboretum 

 at Plainfield, Mass., from which the following, having reference probably 

 to this species, is copied : 



Some of the foreign birches in the arboretum and other localities about Boston 

 have been killed by the attacks of boring larvae, of a beetle belonging to the genus 

 Agrilus, and probably an introduction from Europe. The insect bores into the trunk 

 and limbs, ultimately killing the tree. Its presence is often indicated by a slight 

 swelling of the bark. 



Among the writer's collecting notes, made previous to his connection 

 with the Department, is one of the capture of this species July 20, 1884, 

 on willow, associated with A. politus Say, the latter a well-known wil- 

 low borer, being observed in greater abundance. This is briefly men- 

 tioned as a willow species in Entomologica Americana (Vol. Y, p. 220, 

 Dec, 1S89). 



To this must be added reference to a note which appeared in letter 

 form under various titles over Mr. Adams's signature in the Buffalo 

 (N. Y.) daily journals of October 9 and 10, 1898. In this letter Mr. 

 Adams called particular attention to the value of the early destruction 

 by burning of all dying or injured birch trees in the infested locality. 

 The identification of the depredator as a species of Agrilus was first 

 made public through a short letter addressed to Mr. Adams by Mr. 0. L. 

 Marlatt, of this Division, and published in the proceedings of the board 

 of park commissioners of the city of Buffalo. (Buffalo News, I^ov. 7, 

 1898.)* 



METHODS OF CONTROL. 



From our present knowledge of the life habits of this insect there 

 are only two methods of control indicated. These are clean cultural 

 practice and the employment of precautionary measures which will 

 serve the purpose of deterring the insects from depositing their eggs 

 upon the trees and from effecting their egress through the bark of in- 

 fested trees. 



It is not probable that the trees can be saved after the borers have 

 once taken possession of them, and the only thing to do is to cut down 

 and destroy them by burning before the following Mayor in time to 

 prevent the issuance of the adult beetles in June. It is of prime impor- 

 tance that the utmost care be observed to effect the destruction of all 

 dead and dying trees before the time for the beetles to issue, for the 

 deposition of their eggs in the early summer, and this applies to every 

 bit of wood of birch, poplar, and willow that may be infested or that 

 may harbor this insect and thus prove a center of infestation to healthy 

 or uninfested growth. 



Some species of Agrilus have been observed to feed freely upon the 

 upper surface of the leaves of their host trees, and it will be worth 



* Since the present article went to press a few similar letters have appeared. 



