ORCHARD HEATING 19 



smudge from the coal as far as retaining the heat is concerned 

 is about as good as that from the oil. The coal heaters are a 

 little harder to get started, their heat is not so easily regulated 

 as with the others. With the oil heaters, the rate of burning can 

 be controlled by adjusting the supply o>f air and in addition to 

 the great ease of starting them, they can be put out by putting 

 on the cover. The oil is somewhat easier to handle than the coal 

 and all points considered, the oil is probably the better fuel to use. 



EQUIPMENT NECESSARY FOR HEATING? 



For a small orchard the oil can be purchased in barrels and 

 distributed to the pots in the orchard by hauling these barrels on 

 an ordinary wagon or on a sled. The oil is much cheaper if it 

 is purchased in carload lots; hence if the orchard is large or if 

 several farmers can combine and buy a carload of oil, after get- 

 ting bids on it then they should put up a storage tank made out 

 of metal or concrete and purchase a special wagon for hauling 

 this oil to the tank and later out into the orchard. The tank 

 should be located if possible, on the hillside so that it may be 

 filled from the wagon by gravity and also because the wagon can 

 be filled from it by driving underneath. If this can not be done, 

 a pump will need to be purchased. Torches should be procured 

 for use in rapidly igniting the crude oil and several high grade 

 thermometers should be distributed throughout the orchard, 

 The heaters should be placed in the orchard in the early spring 

 and after being filled with oil should be covered with the lid to 

 keep the rain out. Arrangements should be made in advance 

 for extra labor at the time of the frost because as a rule the 

 heating has to be done several nights in succession and during 

 the day time the pots have to be refilled. 



FORECASTING FROST 



In order successfully and profitably to protect an orchard 

 from frost one must know when one should heat, because ob- 

 viously fuel should not be burned when the frost is not severe 

 enough to cause damage and when danger is near the fires 

 should be lighted to prevent the injury. 



The Section Director of the U. S. Weather Bureau at Salt 

 Lake City would gladly loan to one orchardist in a locality, called 

 the key station, a standard maximum thermometer, a standard 

 minimum thermometer (in some cases a thermograph) and a 

 shelter for these instruments. The orchardist is expected to 

 read the instruments each morning during the blooming period 



