HOW TO CONTROL THE PEAR THRIPS. 



Table V. — Emergence ofthripsfrom samples taken from orchard in November and Decem- 

 ber and kept in cages at laboratory, Suisun, Cal. 



Fig. 3.— The pear thrips: Eggs, high- 

 ly magnified. (Original.) 



By the time the fruit buds have swollen sufficiently to separate 

 the bud scales slightly at the tip the adults force their way within, 

 feeding upon the tenderest portions inside the buds. When the 

 thrips are present in sufficient numbers the 

 buds are completely destro3'^ed and the trees 

 fail entirely to bloom. 



Eggs. — As soon as the first leaf surfaces 

 or fruit stems are exposed egg laying usually 

 begins, depending somewhat on the variety 



of fruit attacked. 

 The first eggs are 

 deposited the last 

 days of February 

 and oviposition 



continues till near the middle of April, being 

 at its maximum, however, from the 10th of 

 March to the 1st of April. Most of the eggs 

 (fig. 3) are deposited just under the epidermis 

 in the fruit stems, young fruit, and leaf 

 stems. The eggs require from five to seven- 

 teen days to hatch, the average time being 

 about eight days. 



Larvx. — By the time the trees are break- 

 ing into full bloom the adults have done 

 most of the damage caused by their feeding, 

 and oviposition is at its height. Many of 

 the earlier appearing adults are dying off and 

 larvae (fig. 4) are beginning to appear in 

 4.-The pear thrips: Larva, numbcrs. The vcry first larvse can usually 

 be found about March 20, and are in maxi- 

 mum numbers on the trees, feeding on the small fruit and young 

 foliage, from the first to middle of April. Reaching their full devel- 

 opment, the larvae drop from the trees, of their accord or with falling 

 calyces, or are blown by wind or knocked off by rain. After the 



Fig 

 greatly enlarged 



