HOW TO CONTROL THE PEAR THRIPS. 



u 



Table VI. — Number of adult thrips emerging from cages containing samples of soil 

 taken before and after ploioing — Landon prune orchard, 1908-9. 



Average number of thrips per cage before plowing 1, 364 



Average number of thrips per cage after plowing and cross plowing 396 



Percentage li-vnng in treated areas as against the number of thrips living in un- 

 treated ground per cent . . 30 



Approximate percentage killed do ... . 70 



In the spring of 1909, 5 J acres of this 16-acre orchard were sprayed 

 three times; twice before blooming, for adults, the first application 

 March 8 and 9, just as cluster buds were spreading, and the second 



Fig. G.— Power sprayer at work in Landon prune orchard, 1909. (Original.) 



application March 16 and 17, just as the white tips of the petals were 

 beginning to show. The third application or larval treatment was 

 put on April 11 and 12, after most of the petals had fallen. For all 

 sprayings a gasoline-power outfit, with tower platform and three 

 leads of hose, as shown in figure 6, was used, two men spraying from 

 the ground and one from the tower to cover the tops of the trees. The 

 material used was the recommended 3 per cent homemade distillate- 



