PKOTECTIXG ORCHARDS AGAINST FROSTS. 271 



i-einovod. This costs tlieni from 21/^ to 3I/2 cents per gallon 

 in tank cars. 



Under Missouri conditions it will be necessary to use on 

 the average one-half gallon per pot per night or with 100 to 

 the acre, a total of 50 gallons of oil per night. This will be 

 sufficient for protecting against the ordinary spring frosts 

 where the temperature only falls to the danger point late in 

 the night. Sometimes, however, severe freezes occur in late 

 spring, when it will be necessary to light the fires as early as 

 11 o'clock in the evening. In this event it would require a 

 gallon of oil and sometimes more to last during the remain- 

 der of the night. It will seldom be necessary to use the heat- 

 ers more than two or three nights in the year. In an abnormal 

 season it will be necessarv to use them three or four nights. 

 If they were used for two nights during the first year the to- 

 tal cost for the pots and oil would amount to only about |20 

 per acre. The pots should last at le ■ st five years, so that the 

 subsequent cost per year per acre would be very light when 

 compared with the value of saving a crop. 



The figures quoted assume that the fruit growers will know 

 when to light the fires and that they will not be lighted unless 

 necessary. If the fires were lighted when it is unnecessary 

 there would be a considerable waste of oil. In fact some in- 

 stances have come under my own observation where fruit 

 gTowers attempted to use smudges made of brush and refuse 

 and they invariably started the fires too soon, and as a conse- 

 quence the fuel was all consumed and the heat and smoke lost 

 before the danger point of cold was reached. 



TEMPERATURE DANGER POINTS FOR PEACHES. 



In the life of the peach bud there are four stages at which 

 the crop may be lost because of injury from cold. The first 

 stage is that of the fully dormant buds as we find them in 

 early winter. At this time under normal conditions they can 

 safely withstand a temperature of eight or nine degrees below 

 zero F., but if the temperature should remain at nine degrees 



