A Consideration of Adverse Temperatures 335 



Coal is used to some extent in heating orchards, as pre- 

 viously noted. It is distributed in wire baskets or sheet 

 metal containers which are placed at intervals throughout 

 the orchard as are the oil-pots. They are less satisfactory 

 on the whole than oil, when the latter is obtainable at a 

 reasonable price, since it is much more difficult to get the 

 coal to burning than it is the oil ; it requires a long time for 

 the fires to give off much heat even after they are started, 

 and in other ways coal is less effective than oil for orchard 

 heating. On the other hand, it has certain advantages so 

 that perhaps the ideal provision for orchard heating combines 

 both the coal and oil equipment. 



In some places, where wood is plentiful and cheap, small 

 wood fires at frequent intervals throughout the orchard have 

 proved as effective as any means available in warding off 

 frosts. 



DOES ORCHARD HEATING PAY? 



The inevitable question which arises is whether orchard 

 heating pays. Prices for heaters, fuel, and the other necessary 

 equipment vary widely. It is not of importance in this 

 connection to estimate specifically cost of equipment. It is 

 obvious, however, that it is considerable, especially when the 

 reserve supply of oil is considered. Probably from S40 to 

 $70 an acre represent conservative limits, though the cost 

 of materials tends to increase rather rapidly. The labor is 

 considerable and much of it is wearing on the individual. 

 Not infrequently a grower has been to the expense of heating 

 several times in a season only to find that a neighbor who did 

 not heat had a full crop of fruit. Or, after heating success- 

 fully for several nights, there comes a temperature so low that 

 it cannot be counteracted, or it may be the reserve supply of 



