No. 4. 



Disease of the Apple tree. 



127 



Disease of the Apple tree. 



In our 2nd number we gave some account of the dis- 

 ease in the Pear tree, and of the borer that does the 

 mischief. Below will be found a similar article, and 

 from the same source, in relation to the Apple tree, 

 and its great enemy. The indefatigable labours and 

 skill of Dr. Harris, have made him eminently success- 

 flil in detecting these insidious depredators, and dis- 

 robing them of the dark mantle in which our igno- 

 rance has heretofore suffered them to remain enveloped. 

 The enemy has been operating so completely in the 

 dark, that we have hardly known where to look for it; 

 whether really in the shape of an insect — in the at- 

 mosphere, in the soil, or in the defective health of the 

 original fruit stock. The Doctor has forced them to 

 the light, and made them hang out their true colours; 

 so that we may now know with whom we are battling. 

 These are interesting subjects, and cannot fail to ar- 

 rest the attention of every one who values his orchard, 

 either for its supply of his own immediate wants, or 

 for the ready cash which its surplus so easily pro- 

 duces him. — Ed. 



The borers of the apple tree have become 

 notorious, throughout the New England and 

 Middle States, for their extensive ravages. 

 They are the larvae of a beetle called Sa- 

 perda bivittata, by Mr. Say, the two-striped, 

 or the brown and white striped Saperda; 

 the upper side of its body being marked 

 with two longitudinal white stripes between 

 three of a light brown colour, while the face, 

 the antennee, the under side of the body, and 

 the legs, are white. This beetle varies in 

 length from a little more than one half to 

 three quarters of an inch. It conies forth 

 from the trunks of the trees, in its perfected 

 state, early in June, making its escape in 

 the night, during which time only it uses 

 its ample wings in going from tree to tree, 

 in search of companions and food. In the 

 daytime it keeps at rest among the leaves 

 of the plants which it devours. The trees 

 and shrubs principally attacked by this borer, 

 are the apple tree, the quince, mountain ash, 

 hawthorn, and other thorn bushes, the June- 

 berry or shad-bush, and other kinds oi' Amel- 

 anchier and Aronia. Our native thorns and 

 Aronias are its natural food ; for I have dis- 

 covered the larvae in the stems of these 

 shrubs, and have repeatedly found the bee- 

 tles upon them, eating the leaves, in June 

 and July. It is in these months that the 

 eggs are deposited, being laid upon the bark 

 near the root, during the night. The larvae 

 hatched therefrom, are fleshy whitish grubs, 

 nearly cylindrical, and tapering a little from 

 the first ring to the end of the body. The 

 head is small, horny, and brown ; the first 

 ring is much larger than the others, the next 

 two are very short, and with the first, are 

 covered with punctures and very minute 



hairs; the following rings, to the tenth in- 

 clusive, are each furnished, on the upper 

 and under side, with two fleshy warts situ- 

 ated close together, and destitute of the little 

 rasp-like teeth, that are usually found on the 

 grubs of the other Capricorn-beetles; the 

 eleventh and twelfth rings are very short; 

 no appearance of legs can be seen, even with 

 a magnifying glass of high power. The 

 grub, with its strong jaws, cuts a cylindrical 

 passage through the bark, and pushes its 

 castings backwards out of the hole from time 

 to time, while it bores upwards into the 

 wood. The larva state continues two or 

 three years, during which the borer will be 

 found to have penetrated eight or ten inches 

 upwards in the trunk of the tree, its burrow 

 at the end approaching to, and being covered 

 only by the bark. Here its transformation 

 takes place. The pupa does not difler much 

 from other pupae of beetles ; but it has a 

 transverse row of minute prickles on each 

 of the rings of the back, and several at the 

 tip of the abdomen. These probably assist 

 the insect in its movements, when casting 

 oft' its pupa skin. The final change occurs 

 about the first of June, soon afler which, the 

 beetle gnaws through the bark that covers 

 the end of its burrow, and comes out of its 

 place of confinement in the night. 



Notwithstanding the pains that have been 

 taken by some persons to destroy and exter- 

 minate these pernicious borers, they con- 

 tinue to reappear in our orchards and nur- 

 series every season. The reasons of this 

 are to be found in the habits of the insects, 

 and in individual carelessness. Many or- 

 chards suffer deplorably from the want of 

 proper attention ; the trees are permitted to 

 remain, year after year, without any pains 

 being taken to destroy the numerous and 

 various insects that infest them ; old orchards, 

 especially, are neglected, and not only the 

 rugged trunks of the trees, but even a forest 

 of unpruned suckers around them, are left 

 to the undisturbed possession and perpetual 

 inheritance of the Saperda. On the means 

 that have been used to destroy this borer, a 

 few remarks only need to be made ; for it is 

 evident that they can be fully successful only 

 when generally adopted. Killing it by a 

 wire thrust into the holes it has made, is 

 one of the oldest, safest, and most successful 

 methods. Cutting out the grub, with a knife 

 or gouge, is the most common practice ; but 

 it is feared that the tools have sometimes 

 been used without sufficient caution. A 

 third method, which has more than once 

 been suggested, consists in plugging the 

 holes with soft wood. If a little camphor 

 be previously inserted, this practice promises 

 to be more effectual; but experiments are 



