34 Farmers' Bulletin 1096. 



TABLE 2. Detailed costs of protecting 40 acres of oranges ivith oil heaters Con. 

 OPERATING EXPENSES Continued. 



Operation Continued. 



Oil, 1914, 13,725 gallons at $0.03 $401.75 



Hauling, at $1.50 per 1,000 20.58 



$422. 33 



Oil, 1915, 575 gallons at $0.03 17.25 



Hauling, at $1.50 per 1,000 . 75 



18. 00 



Oil, 1916, 15,525 gallons at $0.04 621. 00 



Hauling, at $1.50 per 1,000 23. 28 



644. 28 



Total for four years 1, 875. 09 



Credit oil on hand, 17,173 gallons, at $0.04 686. 92 



Hauling, at $1.50 per 1,000 25. 75 



712. 67 



Net cost, 4 years 1, 162. 42 



Average cost per year $290. 60 



Distributing, filling, firing, taking in, cleaning, and painting heaters : 



1913-14 , 199. 88 



1914-15 204. 63 



1915-16 340. 90 



1916-17 336. 70 



Total cost for four years 1, 082. 11 



Average cost per year 270. 52 



Total annual cost for 40 acres 1.062.55 



Average annual cost per acre r 26. 56 



Detailed average annual cost per acre. 



Interest $4. 57 



Depreciation . 7. 96 



Operation : 



Fuel 7. 26 



Labor 6. 76 



$26. 55 



BEST METHODS OF HANDLING ORCHARD HEATING 



The fact can not be emphasized too strongly that if orchard heat- 

 ing is to be practiced successfully, it must be handled with as much 

 care and attention as spraying, fumigating, or any other necessary 

 farm work. The secret of success will be found in adequate equip- 

 ment, good judgment, attention to detail, and extreme vigilance. 

 An inadequate number of fires to the acre may often be worse than 

 none at all, as the costs of firing may have to be added to the loss 

 of the crop. 



Whenever the temperature approaches the danger point the 

 thermometer in the orchard should be watched closely and, if pos- 

 sible, the rate at which the temperature is falling should be deter- 

 mined. If the temperature is falling rapidly the firing must be 

 begun early if the heaters are to be all lighted before the danger 

 point is reached. With a little practice it is often possible to tell 

 with considerable accuracy by inspection of the fruit or blossoms, 



