FOR PROFIT. 155 



order to obviate this, the American and Canadian 

 Orchadists have very successfully introduced smother 

 fires, either made from the refuse prunings, weeds, 

 etc., on the land, or better still, by the use of the 

 Colorado Orchard Heaters, which give out more heat 

 than a bonfire, are inexpensive to work, and can be 

 quickly set going. The inventors say one man can 

 light an acre in three minutes. They require no 

 further attention, being self-feeding, and clean them- 

 selves. They burn for four hours with 151b. of 

 ordinary coal, this time being as a rule sufficient to 

 ward off the fatal early morning frosts, but they can 

 be charged with more coal to last double the time. 

 In the bonfires the smoke spreads like a cloud, and 

 thus raises the temperature and prevents the sun 

 striking the blossom when frozen. An interesting 

 trial took place at Hounslow. Fifty Colorado Heaters 

 were started at about 25 feet apart, covering an acre 

 of trees. The temperature was taken at 7-ft. from 

 the ground, and from 6.20 to 10.20. The outside 

 thermometer gave 32 degrees (freezing point), while 

 the Heaters raised the area operated on to 35, 36 

 and 40 degrees, thus saving the crop. The cost of 

 these Heaters is 2/- each for 100, and cheaper for 

 quantities of 300 — being at 1/6 each. 



They have been tried by several large fruit growers 

 with success, and there is no doubt that fruit crops 

 have been saved by their use. 



In smother fires the direction of the wind must be 

 considered, and the annual prunings and weeds might 

 be saved for the purpose of these bonfires, but if 

 not used, we strongly recommend all rubbish and 

 prunings to be burnt, as such rubbish only harbors 

 insects and pests of all kinds. 



