CHAPTER VII. 



PREVENTIVE SPRAY WORK CONDUCTED BY ORCHARDISTS. 

 GENERAL CONSIDERATION OF THE AUXILIARY WORK. 



While planning the experiments already detailed it seemed desirable 

 to set on foot a similar line of work among peach orchardists in gen- 

 eral. It was thought that several advantages could be attained from 

 such auxiliar}^ and coincident work: (1) It would indicate the effective 

 ness or noneffectiveness of the sprays recommended, in controlling curl 

 under the various conditions of variety, situation, soil, temperature, 

 atmospheric humidity, seasonal variations, etc. , existing in the many 

 peach-growing sections of the country. (2) It would eliminate the 

 personal element of the other experiments being conducted, and 

 would introduce various new conditions of orchard work, thus point- 

 ing out the efficiency or needs of the general grower and indicating 

 what features of the work should receive special attention in offering- 

 final recommendations. (3) It would introduce the methods of treat- 

 ment in many peach-growing centers, and by means of the object' 

 lessons thus set up, it would effect a much more rapid and general 

 adoption of such spraying methods than could be hoped for otherwise. 



In advance of the inauguration of this work, which was begun in 

 the fall of 1893, correspondence was opened with over 1,600 peach 

 growers in all peach-growing centers of the United States. To each 

 of these growers was sent a circular describing the nature and cause 

 of peach leaf curl, outlining a series of spraying tests which it was 

 desirable to have conducted for its prevention, and supplying the 

 spray f ormula? known to have given good results in California. Each 

 grower was given the facts necessary to enable him to carry out the 

 work, and was requested to furnish the Department with the results of 

 his experiments. 



A very large number of growers expressed their willingness and 

 desire to assist in conducting these experiments, and a very consider- 

 able number have done so in many of the peach-growing centers. It 

 may also be said that the number of growers who have adopted annual 

 spraying methods as a result of this introductory experimental work 

 is large and is constantly increasing. In fact, the spraying of peach 

 trees for curl has become very general in many of the peach-growing 

 centers of the United States where the disease prevails. 

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