March, 1910 



AMERICAN HOMES AND GARDENS 



117 



Open Air Orchard Heating 



By W. Frank McClure 



'(^f^mmfm^:^?^! 



jHE process of artificially heating the air in 

 an orchard, on a dangerous fall in tem- 

 perature, could be demonstrated in no bet- 

 ter way than by the description and illus- 

 trations herewith presented of the recent 

 success in saving fruit in the Grand Valley 

 in Colorado. The 1909 crop of fruit, 

 from the Palisades above to Loma below, valued at 

 $3,000,000, owes its existence to a unique battle which 

 was waged against Jack. Frost at a time when the fruit 

 was at its tenderest age. Bv unusual generalship and 

 the work of hundreds of volunteers, the temperature in these 

 orchards was actually raised eight and nine degrees over 

 twenty-seven miles, and a precedent was established which 

 will mean much to the fu- 



ture. In California it is said 

 that the temperature has 

 been raised heretofore in 

 some single orchards two 

 or three degrees, but never 

 to eight degrees, and never 

 before has the work been 

 carried on over so great an 

 area. Plans are now on 

 foot to have everv bear- 



Spraying the trees with apparatus which also conveys oil to the pots 



many difPerent types, some burning oil for fuel and some 

 coal, and placed at intervals in the orchard, after the manner 

 shown in the accompanying photograph. 



Oil was carried to the pots in wagon tanks equipped 

 for the purpose. Spraying machines were also used in dis- 

 tributing the oil. 



A large supply of lighters was kept in readiness in a 

 dry place. Many of these lighters were made by wrapping 

 waste about a twisted wire. 



All operations were directed from Grand Junction. 

 Weather stations established over much of the territory, 

 and equipped with thermostats, when the threatening 

 weather arrived, made half-hourly reports on the tem- 

 perature to Grand Junction. 



When finally the danger 

 point was approaching, 

 warning was sent to all 

 the ranchmen to light the 

 fires. Volunteers also in 

 nearly all walks of life 

 made their way in automo- 

 biles and wagons and on 

 bicycles over the entire 

 area. The Trades and 

 Labor Assembly adjourned 



Raising the temperature in a Colorado orchard 



A photograph taken late in the evening, showing coal pots with draft 



ing orchard in the Grand Valley protected by next season, 

 not that there is any likelihood of frost every spring in 

 this section, but because the protection against possible 

 repetition of this year's experience is considered cheap in- 

 surance. Representatives of other fruit-growing sections 

 have also recently visited the Grand Valley, sent there from 

 their several communities to' learn more of the recent ex- 

 periment. 



The raising of the temperature over this large area was 

 accomplished by means of some 300,000 smudge pots of 



its meeting, and worked all night rendering assistance. Men 

 worked in shifts, some at night lighting the fires, and others 

 in the daytime filling the pots. Even women assisted in 

 the work. The campaign in all lasted four days. So well 

 did this orchard-heating idea work, that while the tempera- 

 ture outside the heated area dropped as low as 20 degrees, 

 within the heated area it did not go below 293/^ degrees. 

 Seventy-five per cent, of all the fruit trees which were in 

 bloom were cared for directly, while even orchards owned 

 by those who were skeptical of the idea were saved bv the 



