28 



BULLETIN 851, TJ. S. DEPARTMENT OF AGRICULTURE. 



APPLYING MATERIAL WITH A "SPRAY GTUN." 



The " spray gun " for applying liquid material was introduced in 

 1916 and is now in general use among the fruit growers of western 

 New York. The shortage of labor and introduction of dust as a 

 fungicide and insecticide had much to do in bringing about its use. 



The gun was introduced after the completion of the principal part 

 of this study, but it has had such a marked effect on labor require- 

 ments that it has seemed advisable to show the amount of spray 

 material applied, the time required, and the total cost of spraying 

 with this new method. In this area practically all spray crews now 

 consist of two men and a team. One man does the driving, the other 

 applies the material with the gun. 



Material and labor costs have advanced since 1915. Commercial 

 lime-sulphur, which formerly cost the farmer 14 cents, now is 18 

 cents per gallon, while lead-arsenate paste has advanced from 8 cents 

 to 15 cents per pound. Man and horse labor which formerly figured 

 at 20 and 15 cents per hour, respectively, are now 30 and 20 cents 

 per hour. 



By considering Tables XYII and XIX it will be noted that, owing 

 to the use of the gun, approximately 40 per cent less of the diluted 

 material is now being applied per acre than formerly, thereby de- 

 creasing the hours of labor. However, owing to increased labor and 

 material costs per unit, the total cost of spraying remains approxi- 

 mately the same. 



There is some question in the minds of many growers whether the 

 new method is as efficient as the old. More or less injury to foliage 

 and fruit has resulted, and many claim the codling-moth larvae are 

 not as well controlled as by the old method. From observation, 

 however, it would seem that the greatest factor in obtaining good 

 results is the man behind the gun. Some growers think they will 

 return to the use of the pole and nozzles for the calyx spray, and 

 sprays that are made on the foliage later in the season. 



Definite conclusion as to the superiority of this new method over 

 the one formerly used can not be drawn until the gun has been in use 

 for a longer period. 



Table XIX. — Labor and material cost per acre (35 trees) for spraying with a 

 crew of two men and two horses, ivith the use of a spray gun (1919). 





Per 

 cent of 

 grow- 

 ers 

 making 

 spray. 



Acres 

 in 10 

 hours. 



Gallons. 



Hours per acre. 



Cost per acre. 





Per 

 acre. 



Per 

 tree. 



Man. 



Horse. 



Labor. 



Ma- 

 terial. 



Total. 



Delayed dormant spray 



71 

 69 

 100 

 72 

 33 



5.7 

 5.5 

 5.3 

 5.8 

 5.2 



176 

 189 

 192 

 185 

 171 



5 

 6 



6 

 6 

 5 



3.8 

 3.9 

 4.0 

 3.6 

 3.9 



3.8 

 3.9 

 4.0 

 3.6 

 3.9 



$1.90 

 1.95 

 2.00 

 1.80 

 1.95 



$4.80 

 2.80 

 2.81 

 2.63 

 2.72 



S6.70 

 4.75 



Calyx spray 



4.81 



Two-week spray 



4.43 



Aug. 1 spray 



4.67 







