186 JOURNAL OF ECONOMIC ENTOMOLOGY [Vol. 5 



years, it was the exception during this spring. Seckels suffered almost 

 as severely as Kieffers, while Bartletts and Clapp Favorites, though 

 showing considerable blighting of blossom clusters in different plant- 

 ings, were not in the main seriously affected. 



In view of the importance of the attacks of the thrips on sweet 

 cherries, the conditions in plantings of this fruit were carefully noted. 

 Such varieties as Black Tartarian, Napoleon Bigarreau, Schmidt 

 Bigarreau and Windsor are the leading commercial sorts, and these 

 were frequented by large numbers of the thrips from the time of the 

 spreading of the winter bud scales to the dropping of the blossoms. 

 As has been commented on by other writers, the most noticeable work 

 of the pest was on the fruit stems which were much scarred as a result 

 of oviposition. From the appearance and the numbers of the wounds 

 it was at first thought that there would be considerable early falling 

 of fruit. Premature dropping of cherries occurred to a slight degree, 

 but in spite of the numbers of the thrips the trees produced satisfactory 

 yields; and the fruit, because of favorable weather conditions, was 

 of superior quality. There is much interest on the part of fruit growers 

 as to the probable effects of oviposition upon the cherry crop because 

 during some seasons there is considerable yellowing of the stems, 

 which is sometimes attended with premature dropping of much of the 

 fruit. The larvae were observed in large numbers under the "husks" 

 or loose calyces of the fruits; and, while an occasional cherry showed 

 abrasions of the skin, the value of the crop was not appreciably affected. 

 The leaves of sweet cherry trees w^ere attacked by both adults and 

 larvse, and as a result of their injurious work the foliage was generally 

 full of holes and sometimes quite ragged in appearance. Apples, 

 apricots, sour cherries, peaches, plums, and quinces, in spite of the 

 numbA"s of the insect, showed as a rule only slight evidences of injury. 



History of Thrips about Germantown. The writer interviewed 

 many growers upon the early history of the thrips in order to account 

 for its presence in a region so distant from its well-known habitat. 

 How^ever, very little definite data was obtained as in the past the in- 

 juries to the trees have been attributed to spraying mixtures and late 

 frosts, and the insect was not recognized as the originating cause of 

 the unfavorable conditions of the trees until this year. From the 

 statements of orchardists it seems that the thrips has been at work in 

 some plantings for at least five years and recently its ravages have 

 become increasingly conspicuous until 1910, when it was generally 

 exceedingly destructive. During that year the yields of Kieffers 

 were much reduced and the losses were large because of the extensive 

 orchards of this variety. The opinion generally prevails that the 

 introduction of the thrips in this region is of recent origin and that it 



