ECONOMIC ZOOLOGY — ENTOMOLOGY. 249 



and to which the name apple root borer is given. Further observations have 

 shown that the species is quite generally distributed throughout the Appala- 

 chian fruit region and that in places it is doing considerable damage to young 

 apple trees. A study of the literature has shown that this species was first 

 described from Massachusetts in 1837 and was reported in 1875, as having been 

 found living on the service tree or shadbush {Atuelanchier canadoiKis) in 

 various parts of that State. It was reported in 1889 as being found occasionally 

 in Massachusetts in June feeding on the leaves of thorn, service tree, and 

 chokeberry. A specimen in the National Museum Is recorded as having been 

 collected at Tryon, N. C, in June on leaves of Oxydendruin. Since the sjiecies 

 is also recorded from Michigan, Peunsj'lvania, and New Jersey, it is thought 

 probable that it occurs throughout the greater part of the eastern United 

 States. 



The injury to the trees is done bj^ the slender, white larva which bores 

 through the sapwood and heartwood of the roots and lower trunk, the burrows 

 through the I'oots frequently extending ouward for several feet and in badly 

 infested trees being so numerous that the roots often die, causing a weakness of 

 the whole tree. The work of the insect is obscure, there being no chips or 

 castings coming to the surface as is the case with the roundheaded apple tree 

 borer. The egg, which is placed rather conspicuously on the bark of the trunk, 

 and the exit holes through which the adult escapes from the wood are the 

 only external marks made by the insect on the tree. In addition to the injury 

 resulting from the damaged roots, the exit holes in the bark admit more or less 

 water, which frequently induces decay of the heartwood. At French Creek, 

 W. Va., 125 apple, 20 pear, and 200 service trees from one-half to 5 in. in diame- 

 ter were cut off a few inches above the ground and, upon examination, showed 

 311, 9, and 342 burrows of Agrilus and 101, 0, and 21 burrows of Saperda, re- 

 si^ectively. The author reports having found the larva to attack apples, 

 pear, wild thorn, wild crab, and service tree. Of the several larval food plants 

 named the aijple and service tree seem to be greatly preferred. 



In the latitude of West Virginia the eggs are deposited in May and June. 

 They are glued tightly to the bark of the trank a few inches above the ground 

 singly or, rarely, in pairs. On hatching out the larva leaves the egg fx*om the 

 underside, bores directly through the bark to the cambium, and thence through 

 the cambium down the trunk to the ground, whence it proceeds onward through 

 a convenient root. After boring through the cambium for a distance of from 

 6 to 12 in. it burrows abruptly into the solid wood, where all the feeding 

 throughout the remaining part of the larval stage is done. After burrowing 

 into the solid wood of the root the larva continues to feed outward from the 

 tree. If the root is long enough the burrow may continue toward the tip for 

 a distance of 3 or 4 ft, after which it turns and is directed back toward the 

 base. It spends its first winter weU out from the trunk, often in a root not 

 more than one-sixteenth of an inch in diameter. It is active late in the fall 

 and early in the spring, and it is thought probable that considerable feeding 

 is done during the winter. " With the coming of warm weather it feeds rapidly 

 back toward the base of the root, and by midsummer it has reached the center 

 of the root system and has begun to ascend the body of the tree. The latter 

 part of the summer and the fall are spent in boring upwax'd through the trunk 

 and in fashioning a pupal chamber. In trees that are quite small pupation 

 takes places within 5 to 10 in. of the ground, but in larger trees the larvje for 

 some reason ascend higher before forming the pupal cells. In apple and pear 

 trees that are as large as G in. in diameter at the base of the trunk it is not 

 unusual for the larvse to ascend 2 or 3 ft. to pupate, and in one case an indi- 

 \idual was found in a 12-year»old pear tree that had burrowed up fi-om the 



