Orchard Heating 267 



The cost of the material for firing varied greatly, depending upon 

 how it was obtained. In some cases, where good cordwood was used, 

 the cost of one firing was given as $2 an acre. However, it may be 

 stated that generally the cost to the acre for one night was between 

 $2 and $2.50. In some cases the cost was estimated as high as $4, 

 but it is quite possible that more material than was necessary was 

 burned, and that a higher price than usual was paid for it. When 

 stable manure and rubbish alone were used, the cost for firing an 

 acre was from 4 to 10 cents. This was because the material was on 

 hand, and the only element of expense was for distributing it. 



Oil-heating, however, is the most dependable means. 

 "No matter how remote a fruit-district may be from an 

 oil-field," writes O'Gara, "there is no question but that 

 oil is the best fuel to be used, especially in large commercial 

 orchards when the labor problem is one of more than ordi- 

 nary importance. There is a great deal of difference in the 

 oils as secured in different parts of the country. For the 

 most part, eastern crude-oils have a paraffine base, while 

 those on the Pacific slope have an asphaltum base. The 

 crude-oil, or petroleum, as it comes from the wells is very 

 rich in gases and the lighter oils, such as benzene, gasolene, 

 kerosene and others, and therefore, is not used as such 

 for orchard-heating. The gases and lighter oils are all 

 removed by fractional distillation, leaving behind the 

 heavier oils and the asphaltum or paraffine base, as the 

 case may be. The fuel-oils on the market are, therefore, 

 residuals, and as such are used for orchard-heating. A 

 residual oil with a paraffine base will burn in the common 

 smudge-pot without leaving behind anything but a little 

 soot; but the oils with an asphaltum base do not. For 

 this reason it is found necessary to remove the asphaltum 

 base in so far as is practicable. Asphaltum does not 

 burn readily in a simple smudge-pot, and therefore, 

 remains behind after the lighter oil has burned. Upon 



