148 The Fruit-Growers Guide-Book 



and do not hatch until the following spring. The cater- 

 pillars feed on the leaves spinning a web as they go. This 

 soon becomes of considerable size and makes an unsightly 

 appearance on the trees. When full grown the caterpillars 

 are about two inches long, somewhat hairy and have a 

 white streak running along the back. On their sides are yel- 

 lowish markings and underneath they are quite black. The 

 worms mature in about six weeks, and make cocoons in 

 sheltered places, issuing as moths in about three weeks. 

 The moths are about three-fourths of an inch long, with 

 a spread of wings covering about one and three-fourths 

 inches. It can be controlled by any of the usual arsenical 

 sprays that are applied for insects, such as the codling 

 moth. 



Insects That Attack the Pear 



Pear Leaf Blister Mite. This insect attacks both pear 

 and apple, although usually more common on the pear, 

 from which it gets its name. It appears on the leaves in 

 the spring at about the time they reach their full size, and 

 cause reddish blisters to appear on the under side of the 

 leaves. 



The eggs are deposited under the outer scales of the 

 buds and hatch as growth begins in the spring. The little 

 mites burrow into the leaves, where they cause the char- 

 acteristic swellings. These swellings in spring are reddish, 

 in summer they turn green and by the latter part of sum- 

 mer have become a dark brown. 



This insect is not at all difficult to control, as any of 

 the mixtures used for controlling scale will keep it in 

 check. Lime-sulphur, kerosene emulsion and miscible oils 

 have all been effective in preventing injury from this insect 

 on both apples and pears. 



Pear Slug. Pear trees are attacked by this insect in the 

 summer and again in the late summer or fall. It feeds on 

 the upper surface of the leaves, leaving only the veins. 

 Foliage thus eaten falls from the tree and leaves the trees 

 bare. This insect during its early stages is a slimy slug, 



