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the infested area it was so numerous last summer as to skel- 

 etonize the foliage of entire orchards as completely as the 

 canker worm does in New England. It is easily distinguished 

 from this latter since the caterpillars are light green, very ac- 

 tive, about one-half-inch long and usually there are only two or 

 three feeding near the center of each leaf. There is no web- 

 bing to gather and enclosing the leaves in masses so character- 

 istic of our native fall web worm or seen to a less extent in 

 the nests of the brown tail moth caterpillar. There are two 

 generations and possibly three each seaspn, the caterpillars 

 feeding until late fall and the insect wintering probably 

 both as pupae and adults. The feeding habit is such that 

 spraying with poison should control the pest very readily. 

 The pear psylla is one of the most destructive of our 

 pear insects and a very difficult one to control. The adults 

 or flies, as is well known, winter in any nearby shelter, us- 

 ually under the rough bark on the trunks of the trees, though 

 frequently taking advantage of the protection offered by ad- 

 jacent stone walls, brush heaps, fence posts, and the like. 

 The insects are active during mild days in winter and com- 

 mence laying eggs with the appearance of warm weather in 

 the spring. These eggs are usually all deposited upon the 

 smaller twigs and fruit spurs before the blossom buds have 

 developed greatly and generally speaking pear growers will 

 find it extremely desirable to make a delayed dormant ap- 

 plication of the lime sulfur wash at winter strength before 

 the blossom buds have separated or pulled apart. This treat- 

 ment means the desruction, if the spraying is thorough, of 

 all the psylla eggs and should be supplemented by clean cul- 

 ture in and about the pear orchard to eliminate any shelters 

 such as brush piles and stone heaps where the insects might 

 linger longer than they normally would and thus, by a de- 

 layed oviposition, vitiate in large measure the benefits, so 

 far as pear psylla control is concerned, to be obtained from 

 this late application. Failure to secure satisfactorv results 

 may necessitate later applications of nicotine and soap for 

 the destruction of the young psyllas any time during the sea- 



