CHAPTER VIII 

 INSECTS AFFECTING THE PEAR AND QUINCE 



A NUMBER of insects attacking the pear and quince are injurious 

 also in the apple orchard. The San Jose scale, the twig girdler, 

 and the codling moth have already been described under apple 

 insects. 



ATTACKING TRUNKS AND BRANCHES 



The Sinuate Pear Borer (Agrilus sinuatus Oliv.). This is a 

 bronze-colored beetle, nearly one-third of an inch long, whose larva 

 bores in trunks and branches of the pear, making tortuous passages 

 in the sap wood. The presence of these borers is frequently indi- 

 cated by a discoloration of the bark above. Since these burrows, 

 if numerous, may result in the girdling of a tree, a large tree may 

 gradually die as the result of an attack, and a small tree may be 

 killed immediately. 



The grub becomes full grown the second year, pupates in the 

 tree, and emerges the following spring, the female at that time 

 depositing her eggs in cracks of the bark. These beetles may fre- 

 quently be seen basking in the hot sun on the trunks of the tree 

 they attack. 



Control Measures. Dying or dead trees or branches should 

 be burned. Repellent washes may be used as in the case of apple- 

 tree borers. The grub may be removed from the burrow with a 

 knife or killed therein by the use of a wire. 



ATTACKING LEAVES AND FRUIT 



Pear-tree Psylla (Psylla pyricola Forst.). This insect was in- 

 troduced from Europe about 1830. It is a brownish hemipterous 

 insect, barely one-tenth of an inch long. Its abdomen has black 

 bands. It has two pairs of wings, which, when the insect is resting, 

 are folded over the back and against its sides in such a way that 

 the insect is made to resemble a very small harvest fly or cicada. 



Life History. The adults hibernate under bark and rubbish, 



emerge in the spring, and lay their tiny eggs on bark or about buds. 



The scarcely visible yellow nymphs attack the petioles, fruit 



stems, and also the leaves (Fig. 132). It has several broods a 



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