HEATING THE ORCHARD. 289 



LIGHTERS AND LIGHTING. 



The most approved method at present is the use of gasoline in lighting 

 the heaters. As this, is a dangerous liquid to handle the best means is 

 to use one of the several patented rapid lighters on the market. These 

 lighters are so arranged that by pressing a spring a given quantity of 

 gasoline is ejected onto the surface of the oil. A torch is attached to 

 the lighter which leaves one hand free for the removing of the covers of 



the heaters. 



In lighting the heaters not more than 25 or 30 per cent of the pots in 

 the orchard should be lighted at first. Usually the temperature drops 

 slowly, and by watching a number of thermometers situated throughout 

 the orchard, always placed at the furthest point away from any lighted 

 heater, the temperature in the orchard can be controlled to exactly the 

 desired degree. 



A very successful way of lighting the heaters where 100 to 120 pots 

 are placed to the acre, is to light every other heater in every second 

 row, thus giving twenty-five or thirty heaters per acre. This is sufficient 

 for from two to four degrees rise in temperature. When this is not 

 sufficient, then to light every other heater in the alternate rows, giving 

 from fifty to sixty pots per acre, sufficient for an increase of from five 

 to seven degrees. Then if more heaters are required, light the balance . 

 in the second row, and then the balance of the heaters in the alternate 

 rows. By this method of lighting the heat is always equally distributed 

 throughout the orchard. 



It is a mistaken idea held by some growers that it is best to raise the 

 temperature in an orchard by increasing the amount of heat produced 

 by each heater already lighted. The government in all its reports sounds 

 a warning in this regard and brings out the point very strongly that 

 "there is no need for great heat locally, but for small fires well dis- 

 tributed." The presence of a large fire creates an upward draft 

 that carries the heat far above the orchard and causes a cold draft to 

 rush in from the sides, replacing the warm air, thus destroying the 

 effect of heating. Numerous small fires well distributed over the orchard 

 do not give a sufficient heat locally to cause any material change in the 

 air currents, thus holding the warm heated air close to the ground, 

 where it is desired. 



Recently there have been a number of experiments with automatic 

 lighting apparatuses. None of these have as yet been perfected, but from 

 present indications there is hope that in the near future there will be a 

 successful automatic lighting apparatus that will be so operated as to cut 

 down the labor required to a minimum and that will enable orchardists 

 having a thousand acres to protect to do so with the few men usually on 

 hand in the spring of the year. ; 



