STATE POMOLOGICAL SOCIETY. 145 



over winter beneath the bud scales, usually of the past season's 

 growth. As spring approaches and the weather becomes 

 warmer, the mites become active and they begin to feed at the 

 base of the growing bud scales. Then, as the leaves push out, 

 the mites migrate to the leaves and piercing the lower epidermis, 

 enter and feed upon the succulent tissue within. The irritation 

 caused by the feeding results in the characteristic blister. 

 Within the blister the eggs are laid and these eggs hatch in a 

 period of about seven days, depending upon climatical condi- 

 tions. In fact, I might say that insect Hfe is largely governed by 

 climate. The young mites, which hatch, continue to burrow 

 around within the blister and when they attain maturity, leave 

 in order to infest other parts of the same leaf, or adjacent leaves. 

 When the mites are especially abundant they will sometimes 

 attack the fruit and fruit stems. I was speaking with Miss 

 Patch for a few minutes yesterday and she informed me that 

 fruit which had been infested with the mite had been submitted 

 to her. The damage to the fruit, however, is usually considered 

 negligible. 



Throughout a season, and especially a season favorable to 

 the mite, there are many generations and often every new leaf 

 as it appears is attacked. During the past season I have been 

 living in the vicinity of Winthrop and Monmouth and have 

 found many orchards quite severely infested. During the 

 drought which we experienced, the mite was very active and 

 caused considerable defoliation in some orchards. 



I have brought with me some apple leaves which are not badly 

 infested, but which show the characteristic blisters. On the 

 pear, the blisters are usually found along the mid-rib, while on 

 the apple they are distributed as a rule along the margins and 

 toward the base of the leaves. Often the blisters are so close 

 together that they coalesce and form darkened areas. The mar- 

 gins of the leaves often break. The leaves also curl when the 

 blisters are numerous. The blisters upon the pear, especially 

 upon the Kieffer, will often appear reddish, while on the apple 

 they usually turn brownish in color. On examining these blis- 

 ters on the lower epidermis, it will be seen that they are notice- 

 ably elevated above the surrounding surface. One or more 

 small openings will be seen in each blister through which the 

 mites pass in entering or leaving the blister. The blisters vary 

 lO 



