1656 



ENCYCLOPEDIA OF PRACTICAL HORTICULTURE 



involves an entirely different concep- 

 tion of the operation than as ordi- 

 narily practiced against other orchard 

 insects. Only the most efficient spray 

 materials should be used, namely, 

 the combination of distillate-oil emulsion 

 and tobacco extract or distillate-oil emul- 

 sion and nicotine solutions. The spray- 

 ing must be thoroughly done and put on 

 the trees when the thrips appear in num- 

 bers, not waitmg till many buds have 

 been destroyed It is strongly advised to 

 use power machines, and growers are 

 urged to use them for all the spraying, 

 and to have a tower platform elevated 

 over the tank so that one man can thor- 

 oughly drench the tops of the trees. It 

 is absolutely necessary to use high pres- 

 sure — from 150 to 200 pounds — and only 

 angle nozzles should be employed, and 

 these must be held close to the bud clus- 

 ters to force the spray directly into the 

 ends of the buds. This is absolutely 

 necessary to secure good penetration and 

 get satisfactory results. Plenty of ma- 

 terial — three to five gallons per tree for 

 pears, depending on the size of the tree 

 — should be used; more liquid is required 

 for large prune trees; large cherry trees 

 may require seven to eight gallons per 

 tree for satisfactory results Only two 

 rows should be sprayed at a time, using 

 three men, one on the tower to spray the 

 tops of the trees, thus reaching all buds 

 pointing upward, and two men on the 

 ground (one to each row) to spray the 

 lower buds and those pointing down- 

 ward or laterally. 



Timing the ApplicatioBs 

 Method 



The spraying must be done on time 

 and for the best results all the trees 

 should be treated within a few days. Dur- 

 ing the season of 1910 more of the failure 

 tb get satisfactory results was due to 

 lateness of application than to any other 

 one cause. Thrips were in the trees and 

 in great numbers before many of the 

 growers purchased their spraying sup- 

 plies, and in many cases half the buds 

 were entirely destroyed and the others 

 badly injured before the trees had been 



given even the first application. The 

 grower should have everything in readi- 

 ness, all materials on hand, concentrated 

 emulsion made up and spray machinery 

 in perfect working order by the first of 

 March and have all other orchard work 

 in such shape that when the thrips ap- 

 pear in numbers the spraying may be 

 done at once and before the buds have 

 been seriously injured by the feeding of 

 the adults. The grower should have 

 enough spray machines to cover the or- 

 chard quickly. At least one good power 

 outfit is necessary for every 30 acres of 

 orchard. 



Schedule of Applications 



In badly infested orchards three appli- 

 cations are necessary. Two of these 

 sprayings should be directed against the 

 adults and one against the larvae, and 

 to obtain satisfactory results must be 

 timed properly. 



First Application 



The first spraying should come as soon 

 as the thrips can be found on the trees 

 in numbers, about March 1st. 



Second Application 



The second spraying, which is also for 

 adults, should come from four to ten 

 days after the first, depending somewhat 

 on variety of fruit, stage of bud develop- 

 ment and rapidity of emergence of thrips 

 from the ground. On pears this will 

 usually be just as the earliest cluster 

 buds are spreading, and on prunes and 

 cherries when the tips of the petals first 

 begin to show. 



Both of these applications are impor- 

 tant and necessary to insure the produc- 

 tion of a good crop of uninjured blos- 

 soms. The nozzles should be held close 

 to the bud clusters and the spray di- 

 rected into the ends of the buds. This 

 makes it necessary that the spraying be 

 done mostly from above. 



Third Application 



The third spraying is for larvae and 

 properly comes just as most of the petals 

 are falling from the trees, depending 

 somewhat upon the variety of fruit. In 

 any case the small, white, active larvae 



