CO-OPERATIVE SPRAYING. 153 



orchard a block was set apart for the demonstration spraying and another 

 block, in every way comparable with the first, was left without spraying 

 as a check on the results of spraying. The exact yields of both market- 

 able and unmarketable fruit from the sprayed and from the unsprayed 

 blocks, or from considerable parts of them, were noted. The net value 

 of the fruits was determined by deducting from the actual prices received 

 by the owners, the estimated cost of picking, grading, packing, hauling, 

 etc. The net value, therefore, was what the fruit was worth on the trees. 



The work was done under all sorts of conditions. The trees varied 

 in age from ten years to twenty-eight years and averaged about eighteen 

 years. In some orchards they had been well pruned, but in more cases 

 they had been pruned little or not at all for some years. In some cases 

 the spraying was hindered by the closeness of the trees and in others by 

 a secondary crop of bush fruits. In some orchards, on the other hand, 

 the trees were conveniently spaced and the ground was free from 

 troublesome bushes. A few orchards had almost every convenience for 

 mixing and applying the spray materials, while others were almost com- 

 pletely without such conveniences. Contrast, for instance, a case where 

 It was necessary to go a half mile or more from the orchard to get 

 water for spraying and where it was then necessary to pump it by hand 

 and lift it up to the spray barrels in buckets; contrast this with the 

 cases where the mixing stations were near the center of the orchards, 

 where a suflQcient supply of water to spray a considerable part of the 

 orchard was held in a large tank filled with a windmill or gasoline 

 engine, and where the supply tank, dilution tanks, etc., were on a plat- 

 form higher than th'fe spray wagon so that the mixtures simply ran down 

 into the spray tank. Under the first set of conditions it often cost 

 more to mix the spray than to apply it, while under the second set of 

 conditions little time was spent in mixing and hauling the spray. Some 

 orchards were provided with efficient gasoline power spray pumps 

 mounted on trucks carrying large spray tanks, overhead platforms and 

 the like to facilitate the work. The other extreme was a poor hand 

 pump with which it was barely possible to maintain pressure for one 

 spray nozzle. The cost of spraying naturally bore very direct relation 

 to the facilities for work in the various orchards. The labor, cost of 

 mixing and applying the spray varied from one and a half cents per 

 gallon under the most unfavorable conditions to only slightly over three- 

 tenths cent per gallon where the conditions were in every way favorable. 

 The average cost of mixing and applying the spray in these demonstra- 

 tions, namely, one cent per gallon, is therefore higher than it need be. 

 at least in commercial orchards. 



Not only did the somewhat unfavorable conditions noted make spray- 

 ing more costly than necessary, but the rather poor average condition 

 of the trees, mostly from crowding and lack of pruning, reduced the 

 average yield of choice fruit materially and indirectly increased the 

 relative cost of spraying. That is, the cost of spraying per bushel of 

 6 



