INSECTS INJURING CHESTNUT LEAVES. 343 



INSECTS INJURIOUS TO THE CHESTNUT. 

 {Castanea vesca.) 



AFFECTING THE TRUNK AND LIMBS. 

 1. The chestnut tree borer. 



Making a zigzag burrow under the bark, and sometimes descending nearly 2 inches 

 towards the heart of the tree where it may spend the winter, a longicorn larva nearly 

 three-fourths of an inch long, dirty white, of much the appearance of the hickory or 

 locust tree borer, and transforming in its chamber into the beetle state. 



Although the chestnut has been supposed to be remarkably free 

 from borers, we have found that in Rhode Island the trunks are quite 

 liable to the attacks of a borer, which we have not yet traced to the 

 beetle, but which will probably prove to be the species next mentioned 

 {Arhopalus fulminans), since this beetle, which is known to inhabit the 

 chestnut, is closely allied to the locust borer in its form, while the larva 

 is also closely like that of Cyllene picta and the different species of 

 Clytus and its allies. The burrows in outline are flattened, cylindrical, 

 being adapted to the broad flattened front part of the body of the larva. 

 The burrows begin as small zigzag galleries about a line in width and 

 4 inches long, making about three turns at nearly right angles in this 

 space ; tiiey are tilled with the castings of the worm ; as the larva grows 

 larger it sinks deep in towards the heart of the tree, when the burrow 

 in the deepest part becomes packed with large, long, curved chips, 

 apparently bitten off by the grub for the purpose of forming a cham- 

 ber, the partition of chips possibly serving to keep out the cold during 

 its winter's sleep. 



2. The brown chestnut beetle. 



Arhopalus fulminans (Fabricius). 



Order Coleoptera ; family Cerambycid^. 



Boring into the trunk, a grub like the foregoing, if not the same insect, which 

 transforms into a dark-brown beetle with dark-blue reflpctions, and the wing-covers 

 crossed by four zigzag fine gray lines. 



The following notice of this beetle 

 is taken from ray Second Report on 

 the Injurious insects of Massachu- 

 setts (1872): 



My attention has been called by Mr. R. B. 

 Grover, a student in the State Agricultural 

 College, to the fact that the Arhopalus fulmi- 

 nans Fabr. (Fig. 129, enlarged twice), one of 

 the family of longicorn beetles, bores in the 

 trunk. I know nothing further concerning 

 its habits nor of the appearance of its grub. 

 The beetle itself is blackish brown, with slight 

 dark-blue reflections ; the legs and antennae 



are of the same color, the latter being scarcely 



1 ,, -i. 1 J mi i ^ ii 1, J Fig. 129.— Chesiuut Borer. -From Packard. 



longer than its body. The top of the head 



and the sides of the prothorax and under side of the body are covered with a pale- 

 gray pile, while certain silver markings on the wing-covers are composed of similar 



