230 The Commercial Apple Industry 



as much material instead of about the same amount of 7 

 gallons a tree. 



The dormant lime-sulfur application is included in the 

 averages of Table XI, but as a rule requires somewhat more 

 labor and of course involves more expensive spray material. 

 Considering the best sprayed orchards, it becomes appar- 

 ent that the spraying operations represent an annual out- 

 lay of at least $40 a bearing acre if depreciation of spray 

 outfit is to be included. 



Spray equipment. 



There is considerable variation in the type of spraying 

 outfits. For the small grower, hand outfits such as bucket 

 or barrel sprayers may be sufficient, but for the commercial 

 grower the power spray is essential. At present the power 

 sprayers operated by gasoline engines are in almost exclu- 

 sive use, although traction and compressed air outfits have 

 been employed with some success. 



Generally speaking, a good spray outfit is a most profit- 

 able investment. For the operator of a moderate sized 

 orchard, the common outfit is a three- or four-horse-power 

 gasoline sprayer with a two- or three-cylinder pump, cap- 

 able of delivering 6 to 9 gallons of spray material a minute 

 under a pressure of 200 to 250 pounds. The 200-gallon 

 tank is most popular. It pays to buy a good sprayer. 

 Heavy repair bills and lack of efficiency very often make 

 the cheap sprayer most expensive in the end. 



For the large commercial grower, the high power gas- 

 oline outfit with four-cylinder pumps and four-cylinder 

 automobile type engines from 10 to 12 horse-power are 

 not uncommon. These large outfits are capable of deliv- 

 ering as high as 15 gallons of spray material a minute 



