1907.] Prevention of Damage by Frost. 



Observation undoubtedly proves that frost does infinitely 

 more damage when the trees and atmosphere are damp than 

 when the airland soil are dry ; in fact, the blossom has often 

 been known to be unharmed after a severe dry frost. It would 

 also appear that damage rarely accrues to the blossoms of hardy 

 fruits, unless the severity of the frost is 4 degrees or more. 



The material burned, both at Pershore and at Toddington with 

 success, was creosote, with the addition of some naphthalene salts 

 and a little water ; the cost was about 4^. per gallon. Each tin 

 pot held one gallon of the fluid, which burned for from three to 

 three and a half hours, according to the amount of wind. 

 In California crude or unrefined petroleum is burned with 

 success, nearness to the oil wells making this a very cheap form 

 of fire. Up to the present it has been impossible to obtain any 

 of this material in England, as apparently the oil is never im- 

 ported here in its unrefined state. 



With an ordinary spring frost it would rarely be necessary to 

 light the fires before, say, an hour before dawn, at which period 

 of the night the frost is usually most severe ; thus, if the fires 

 are lit at 2.30 or 3 in the morning, to burn till, say, 5.30, the 

 critical time would be covered. In a specially severe case, as 

 on April 26th last year, when such enormous damage was done* 

 it was necessary to ignite the pots at 10 p.m., the frost being 

 then some 4 to 6 degrees, with a steady increase to 12 degrees 

 at Pershore and 18 degrees at Toddington at 4.30 the following 

 morning, In this instance it was found necessary to refill 

 the tins between 1 and 2 o'clock in the morning, and they then 

 just lasted over the dawn. By means of a can with a Long 

 spout, the pots may be filled up without danger while still 

 alight . ( )ne tilling, however, at the time above Stated, should be 

 sufficient in a frost of ordinary length and severity. In order 

 to insure success, about forty pots should be used to the acre. 



Taking the acre as a square, the pots should be dis- 

 tributed approximately as shown on the plan. In this case 

 the wind is from the south-west. Should the wind be from 

 the north-east, the pots along lines AH and 1H would be moved 

 to lines Al) and DC. 



W hite stakes or signals of some kind should be placed at the 



endsof all rows as an indication of the whereabouts of the pots, 

 which are sometimes difficult to find in the darkness. The pots 



