SPRAY MANAGEMENT 



21 



Since the tasks and the actual work done are so different on the 

 various farms, no one measure gives an adequate comparison. How- 

 ever, three measures — namely, ( 1 ) gallons of spray applied per machine 

 and per man hour, (2) the machine hours and man hours used in sprav- 

 ing per mature tree and (3) the machine and manhours used in applving 

 the calyx spray per box of apples, give an indication of the differences 

 in efficiency. 



The gallons of spray applied per machine hour ranged from 45 to 

 over 300. This includes the refilling and travel to and from the orchard 

 as well as the actual application. The variation in gallons of spray ap- 

 plied per machine hour (Figure 14) was from 45 to 122 for the small, 

 126 to 200 for the medium, and 162 to 308 for the large machines, with 

 averages of 86, 153, and 239 respectively. 



GALLONS PER MACHINE HOUR 

 280 



240 



200 



I 60 



120 



80 



40 

 



^. 



SMALL 



MEDIUM 



LAHGE 



Figure 14. — Average total gallons of spray used per machine hour 

 by small, medium, and large machines 



The gallons of spray applied per man hour ranged from 22 to 145 

 (Fngure IS). The variation was from 22 to 88 for the small, 52 to 111 

 for the medium, and 74 to 144 for the large machines, with averages of 

 49, 86, and 105 respectively. 



The time required to apply spray per mature-tree equivalent is a 

 practical comparison between farms since the age of the trees was taken 

 into account in estimating the size of the orchards. With this measure, 

 also, the range in machine use and man labor required varied widely on 

 the 40 farms as indicated in Figures IS and 16. • 



Since yields vary from year to year in the same orchard and also 

 between orchards, for comparison the man hours and machine hours 

 were related to the expected normal yield for each orchard. Twenty- 

 three of the 40 operators used less than .04 machine hours per bushel, 1 1 

 used between .04 and .08 hours, and eight were over .08 machine hours 

 per bushel. The man hours required followed a similar curve since two- 

 men crews represent the usual combination. Seventeen of the opera- 

 tors used between .04 and .08 man-hours' spraying per bushel. Seven 



