DETERMINING COSTS OF THE SPRAYING PROGRAM 353 



the hose in a cool, dark place, since it deteriorates in heat and 

 light. Coil it over a barrel elevated off the ground, or stretch 

 it out on a bench or shelf in such a way that it will drain out 

 completely. Do not suspend the hose on nails or from a few 

 points, as cracking is likely to result. 



In the spring, get the machine out ahead of time; go over 

 all the parts and "tune'' it up ready for active use. 



The care of the duster is simple. Drain the engine at the 

 end of the season, clean the hopper thoroughly, and coat with 

 heavy oil or grease all parts subject to corrosion. If dormant 

 dusts are used which cake on the machine parts, especial care 

 must be taken to clean the machine well. 



6. Determining Costs of the Spraying Program. Costs of 

 the spraying program depend upon a number of factors. The 

 cost of the materials themselves may be easily determined, if 

 the dilutions used, the number of applications to be made, and 

 the average amount applied per tree or other unit are known. 



The cost of making the applications is so variable that av- 

 erage figures are of little value to the individual grower. The 

 price of labor, the capacity of the outfit, the accessibility of 

 water and other supplies, and the topography of the land are 

 among the factors that determine costs of application. 



In the Hudson Valley of New York, in 1931, it was found 

 that the average cost of spraying for the season was $2.57 per 

 100 gallons of spray applied, or $15.68 per acre, which would 

 indicate that slightly over 600 gallons of spray material was 

 applied per acre. It must be stressed that this is not enough 

 to give complete control of insect and disease injury in a 

 normal season on full-grown trees. It is merely an average for 

 509 orchards where the number of applications varied from no 

 spray on 23 orchards, to six or more sprays on 57 orchards. 

 Although the trees ranged from newly planted to some over 30 

 years of age, the average for trees in the 486 orchards (4319 

 acres) that were sprayed was 3.8 applications at a rate of 

 5 gallons per tree per application. To grow a crop of good 

 quality it is rarely possible to spray less than six times in the 



