FROST 



FROST 



1285 



French chemist, smudges have been used for centuries 

 on the plains of Cuzco, Peru, on still clear nights by 

 Indians, to retard the loss of heat from the soil. This 

 practice was inherited by them from the pre-Spanish 

 civilization. From the fragmentary pieces of hterature 

 we are able to find concerning the matter of frost-pre- 

 vention, there is no doubt that the practice has been 

 more or less common from the most remote times to 

 the present day. 



It is only in recent years, however, that the matter 

 of frost-prevention has been scientifically investigated. 

 The literature on the subject has been, until very 

 recentl}', of very httle importance, because the methods 

 advocated were very crude and could not be used by 

 the commercial fruit-grower. However, during the 

 1880's and early 1890's, the French vine-growers did 

 some remarkable work. Even at that time, they used 

 heavy oil and tar as fuels, placing these in flat ironware 

 dishes much the same as the modern practice of using 

 smudge -pots with 

 crude-oil. There had 

 also been devised sys- 

 tems of automatic 

 lighting operated by 

 a mercuric column, 

 not very much unlike 

 some of our more re- 

 cently patented auto- 

 matic alarm thermom- 

 eters and self-light- 

 ers. About the same 

 time that the French 

 vine -growers were 

 perfecting their 

 work in frost-preven- 

 tion, the Cahfornia 

 and Florida orange- 

 growers were also 

 making experiments 

 along the same hne. 

 The first successful 

 attempt to prevent 

 frost -injury by the 

 use of heating de- 

 vices on a large scale 

 occurred in California 

 about, 1896. Edward 



Copely is credited with inventing the wire coal-basket 

 as well as a machine to make it cheaply. These bas- 

 kets were filled with kindling and about twenty-five 

 pounds of coal, twenty-five to thirty baskets being pro- 

 vided to the acre. They were suspended by wires to 

 hmbs of trees. The first use of oil of which there is a 

 record was by Everett at Arhngton, California; and the 

 first use of hot water was by Meacham, at Riverside, 

 California. Later, J. P. Bolton, of the United States 

 Weather Bureau, stationed at Fresno, California, 

 devised an oil-pot for use in the vineyards during the 

 period of spring frosts. 



The occasion for considerable activity in the matter 

 of frost-fighting at this time was due to a very severe 

 frost in December, 1895, causing great damage to the 

 orange and lemon groves in the Riverside section. It 

 may be said that the beginning of frost-fighting in a 

 commercial way dates from this time. The Riverside 

 Horticultural Club in the winter of 1897-98 took 

 an active interest, and many experiments were con- 

 ducted, using all sorts of devices for adding moisture to 

 the air by means of fires of damp straw and stable 

 manure, evaporation of water by means of evanorating- 

 pans, sprayers and sprinklers, and by irrigation of the 

 orchards. Boilers were also used with connecting pipes 

 whereby steam was generated and carried to the dif- 

 ferent parts of the orchards. Direct heating of the air 

 by means of fires was also tried and proved to be the 

 most .successful method of preventing frost-injury. 



1586. Method of protecting windward side of an orchard by doubling the 

 number of orchard-heaters. 



The deciduous fruit-growers of the Sacramento 

 Valley, California, also practised orchard-heating more 

 or less successfully, adopting the methods emploj'ed 

 by the citrus fruit-growers of the South. It is remark- 

 able that some of this work did not bear so good 

 results as it should. Fully ten years passed without 

 any advance having been made in the methods of 

 orchard -heating. About 1906, a renewed interest 

 was taken in the work and since that time orchard- 

 heating has been given scientific study. Within 

 the last four or five years the fruit- and vegetable- 

 growers throughout the United States have taken 

 much interest in the practice of protecting their 

 crops from frost-injury, and it has become a recog- 

 nized part of orchard work in districts in which frosts 

 regularly occur. 



The hterature on the subject has now assumed con- 

 siderable importance since it is the result of scientific 

 investigation of frost-injury and frost-prevention at 



the hands of scientific 

 men. There are many 

 important articles 

 and bulletins on the 

 subject. 



The losses occa- 

 sioned by frost in the 

 citrus and deciduous 

 fruit districts of the 

 United States often 

 reach enormous pro- 

 portions. It has been 

 impossible to secure 

 accurate information 

 as to what the aver- 

 age annual loss has 

 been over a period of 

 years; but it is safe 

 to say that the loss 

 would appro.ximate 

 $10,000,000 a year. 

 If one takes into con- 

 sideration the freezes 

 which occurred in the 

 citrus belt in Florida 

 during 1880, 1884, 

 1886, 1894, and 1895, 

 where not only the 

 trees themselves were killed, the lo.ss 

 It is estimated that the 



fruit but the 

 would average still greater, 

 freeze of 1894-95 destroyed 3,000,000 boxes of oranges 

 in the Florida groves. Although the citrus industry in 

 California had not yet reached large proportions, the 

 losses were correspondingly heavy. In January, 1913, 

 the losses in the southern California citrus district 

 reached the enormous sum of $50,000,000, all of which 

 might have been saved by means of the present methods 

 of frost-prevention. Deciduous fruits have suffered quite 

 as heavily from frost-injury. Very often almost the 

 entire crop of fruit throughout the eastern and southern 

 states is a complete failure. In the middle West, 

 especially in Colorado, the one great drawback to 

 fruit-growing has been the danger of damage by frost. 

 This has also been true of the deciduous fruit districts 

 of the inter-mountain and Pacific coast states. How- 

 ever, since the advent of the present methods of pro- 

 tecting against frost-injury, much security has been 

 added to deciduous fruit-growing. 



The problem of preventing injury to plants from 

 frost may be classified under the following heads: 



1. The prediction of frost, and the issuance of 

 adequate frost-warnings. 



2. The construction and use of devices and appa- 

 ratus to be used in frost-prevention. 



3. The cost of orchard heating. 



4. The physics of orchard-heating. 



5. The use of electricity in frost-prevention. 



