INSECTS INJURIOUS TO FRUITS. 89 



mature, undergoes its changes in the ground where it also re- 

 mains during the winter. There are several broods each season. 

 The slugs eat off the green surface of the foliage, leaving it 

 skeletonized. It attacks the cherry, plum and rose as well as 

 the pear. 



Remedies. The remedies are the same as for any of the 

 leaf-eating insects, Paris Green and Pyrethrum Powder being 

 most commonly used. Dusting the leaves with air-slaked lime 

 is also a good remedy. 



The Pear Psylla (Psylla pyricola). This is a minute insect 

 that has occasionally done much injury to pear trees by sucking 

 the sap. It is so small as to be seen with difficulty with the un- 

 aided eye. In severe attacks old trees put forth but little growth, 

 new shoots often wither and drop in May, the leaves turn yellow 

 and the fruit prematurely ripens in midsummer and falls off. Its 

 presence is also indicated by the honey dew which is excreted 

 by the insect in large quantities so as to cover the tree and 

 even the vegetation under it. In this sweet solution a kind of 

 fungus soon starts and smears the tree with a blackish coating. 



The mature insects pass the winter hidden in crevices un- 

 der the loosened bark on the trunks and limbs of pear trees. 

 During warm days they crawl about. In the first warm days 

 of spring the egg-laying season begins. The eggs are laid in 

 creases in the bark and in the old leaf scars. In two or three 

 weeks they hatch into what is known as "nymphs," which first 

 locate along in the axils and petioles of the leaves. As these 

 nymphs grow, they change their skin and in about one month 

 become full grown with wings, and resemble the harvest fly 

 in miniature. They can jump like a flea and fly away upon the 

 slightest unusual jar. 



Remedies. There are several natural enemies that help to 

 hold the pear psylla in check, among which are the lace winged 

 fly and the red ladybug. The most effective treatment seems to 

 be spraying in the spring with kerosene emulsion, applied with 

 considerable force to destroy the young. The mature insect is 

 not easily reached in this way. 



Insects Injurious to the Peach. 



Peach Twig Borer (Anarsia lineatella). When the buds of 

 the peach begin to open in the spring, a small, brownish larva 



