34 N, H. Agricultural Experiment Station [Bulletin 257 



Depreciation was estimated in each case with reference to the condi- 

 tion of the machine. A total of $934 was allowed for depreciation for 

 the three years, or an average of $30 per farm per year. The labor 

 for repairs at 40c per hour for all farms was $277, horse labor for 

 repairs $16, and expense for repair parts and shop work was $240. In- 

 terest on investment at 5 per cent, was $461, and estimated gasoline 

 and oil came to $159.04, making a total for spray machine costs of 

 $2,087.10. 



On this basis, the average cost was $118.52 per 1,000 mature tree 

 units, $19.83 per 1,000 boxes normal yield and $17.99 per 1,000 boxes 

 actual yield. 



No. 12 had a high machine cost of $297.25 per 1,000 trees on ac- 

 count of a large machine on a relatively small orchard. The situation 

 here as is often the case is unavoidable. The grower in purchasing a 

 durable machine must anticipate the needs of the orchard ten or more 

 years in advance. 



No. 2 had a large cost on account of the large amount of total spray- 

 ing done which made the repair work on two machines relatively high. 

 The machine cost was lowest on Farm 9 where a hand pump was used 

 but, of course, the expense of operating the outfit more than made up 

 for the low cost. 



Spray Material Cost 



As described under labor in spraying there were great variations 

 in the number of sprays applied. In addition, certain farms put on a 

 greater amount of spray per application. Farm 2 not only uses a 

 larger total quantity of liquid than any of the farms, but in addition 

 an oil spray, an expensive material, was put on one year for red mites. 

 Farm 7 used dust which is higher in cost than liquid spray material. 



When computed on the basis of mature tree equivalent, (Table 23) 

 the average spray material cost was $436.40 per 1,000 trees. Nos. 2 

 and 7 had a cost of over $500 per 1,000 trees. Farms 1, 3, 4, 9 and 12 

 had costs between $300 and $500. Farms 5, 6, 8, 10 and 11 had costs 

 below $300. 



When computed on a basis of normal expected yield, the average 

 cost of spray material was $73. Farm 7 had a cost of $121.84 per 

 1,000 boxes. Farms 2, 3, 4, 9 and 12 had costs between $50 and $100 

 and farms 1, 5, 6, 8, 10 and 11 had costs under $50 per 1,000 boxes. 



When computed on a basis of actual yield, the average cost of spray 

 material was $66.24 per 1,000 boxes. No. 7 had a cost of $141.73 per 

 1,000 boxes. Farms 2, 3 and 12 had costs between $50 and $100. 

 P'arms, 1, 4, 5, 6, 8, 9, 10 and 11 had costs below $50. 



The formula used for most spraj^s was 2 to 2i/2 gallons liquid lime- 

 sulpliur, and 3 to 4 pounds lead arsenate per 100 gallons of water. 

 Some also added one pound calcium caseinate spreader, and rarely nico- 

 tine sulphate at the rate of % to 1 pint was deemed necessary. Eight 

 to nine pounds of dry lime-sulphur was sometimes used in place of 

 the liquid concentrate. 



Total Cost of Spraying 



With the assumed rate per hour, the total cost of spraying averaged 



