ORCHARD INSECTS OF THE PACIFIC NORTHWEST 



37 



a single fruit. They usually disappear as the fruit ripens, but persist 

 on certain varieties, such as the Mcintosh, Northern Spy, and Yellow 

 Newtown. Badly spotted apples must often be put in a lower grade. 

 The spots are the result of egg punctures made by the flower thrips 

 (Frankliniella tritici (Fitch)) and probably other species. The thrips 

 normally live in dandelions and other flowers, but are attracted to the 

 apple blossoms and lay many of their eggs in the newly formed fruits. 

 The thrips larvae emerge from these egg punctures, leaving small 

 holes in the skin of the apples. These holes become the central spots 



Figure 45. — So-called "pansy spots" caused by the flower thrips. 



of the "pansies." The irregular whitish areas that form about these 

 centers as the fruit grows result from the presence of the eggs in the 

 apples. Nicotine sulfate (40 percent nicotine), in the proportion of 1 

 pint to 100 gallons of water, to which is added several pounds of soap 

 in solution or a pound of casein spreader, will effect some degree of 

 control if used when the trees are in full bloom ; or the nicotine may be 

 added to the calyx spray. 



Pear Thrips 



The pear thrips (Taeniothrips inconsequens (Uzel)) occurs on pears, 

 but in the Pacific Northwest it is more serious as a prune pest, and it 

 is therefore discussed under that heading (p. 56). The recommenda- 

 tions given there also apply to pear trees, except that where it is 

 necessary to control scab, oil should not be used, but nicotine sulfate 



