Diseases and Pests of the Apple and Their Control 233 



grower resorts to this practice when he feels that his acre- 

 age is insufficient to warrant the purchase of a power outfit. 



In considering custom spraying, two decided disad- 

 vantages weigh heavily against this practice. In the first 

 place, the value of spraying and its relative cost may only 

 be measured by its efficiency. No matter how cheap the 

 cost, careless spraying is expensive. To be efficient, a 

 spray must be applied at the critical period. If one has 

 to wait for a custom sprayer, very often the value of the 

 spraying is partly lost. The second reason is that while 

 figuring only labor and material costs the hired sprayer 

 may be cheaper, it is considerably less efficient. On sixty- 

 nine fruit-farms studied in the Yakima Valley, thirty- 

 nine growers owned their own sprayers and thirty hired 

 their spraying done. In every instance the custom sprayer 

 applied on the average of one-third less material to a tree. 

 It is quite likely that in every instance this was false 

 economy. The hired outfit will not perform the careful 

 work which a grower himself will do. 



It is not to be concluded from this discussion that the 

 small orchardist is invariably justified in owning a power 

 sprayer. It has been found that the average depreciation 

 and upkeep of a power spray outfit amounts to practically 

 25 per cent a year. Thus a $500 sprayer investment 

 means an annual outlay of $125 in addition to labor and 

 material. On a five-acre orchard, this cost alone would be 

 $25 an acre. It is doubtful whether the orchardist with 

 less than ten acres is justified in owning a power sprayer. 



Regional spraying notes. 



The northeastern states. The commercial apple- 

 growers in Michigan, New York and New England fear 



