522 



Lime-Sulphur Wash 1 as a Fungicide. [oct., 



the opening at the top larger or smaller at pleasure. About 

 a gallon of crude oil is placed in these receptacles and lighted 

 when the thermometer drops to danger point. If the frost is 

 very severe the top is taken off completely, the combustion 

 in that case being more rapid and the temperature more quickly 

 raised. Experiments have shown that by aid of these pots 

 burning crude oil, the temperature can be raised from 8 to 

 12 degrees, and in those orchards where this system was used 

 during the late frost the crop has been entirely saved. One 

 hundred such pots are used for the acre, fifty being lighted at 

 one time. When the contents are consumed of the first fifty, 

 then should the frost continue, the second fifty are lighted, 

 the consumption of oil thus being regulated to the severity 

 of the frost. It has been proved beyond doubt that by this 

 system of smudging the complete crop can be saved even 

 when the thermometer sinks as low a i8° or 20° F. Un- 

 fortunately where apples and pears and the hard stone fruits 

 are grown the smudging, if done at all, is done principally by 

 the more primitive method above mentioned. 



The small fruit, such as raspberries, blackberries and straw- 

 berries promise well, and doubtless will be a full crop. Apples 

 and pears grown in Colorado supply not only the local market, 

 but the best quality are sent to the large eastern cities as well 

 as to San Francisco and Los Angeles. Consignments have 

 been sent to England and when properly packed have arrived 

 in fine condition and have been pronounced most excellent. 



The United States Department of Agriculture . draws atten- 

 tion* to some experimental trials of a lime-sulphur wash for 

 the prevention of fungus diseases, the 

 Lime-Sulphur Wash results of which are regarded as ex- 

 as a Fungicide. ceedingly encouraging, though the wash 

 has not as yet been sufficiently tested to 

 enable it to be definitely recommen&ded. This wash has 

 previously been used against San Jose Scale and other insects 

 of that type {Journal, November, 1906, Vol. xii, p. 497), but 

 it has now given satisfactory results against several fungus 

 disease of the apple and peach, and it is likely to prove of special 



* Circular No. I, Bureau of Plant Industry. 



