338 



COXTROLLIXG IXSECTS AXD DISEASES 



The stationary plant consists essentially of a pump driven 

 by electric or gasoline power and a mixing unit for prepara- 

 tion of the spray materials, at a fixed point, with a pipe system 

 of mains and laterals extending throughout the orchard, 

 equipped with risers for hose connections at regular intervals. 

 The spray material is applied to the trees in the usual manner 

 by means of hose and rods, or guns, by men who work through 

 the orchard, connecting the hose at convenient points. 



Some of the advantages of such a system are at once ap- 

 parent: 



1. Spra3ang may proceed on schedule on wet or rough land. In the 

 West, irrigation and the use of the portable sprayer often present a diffi- 

 cult problem. In all sections periods of hea^T rains often interfere seri- 

 ousl}^ with the spraying operations, because the ground is too soft to haul 

 the machines over it. In sections where hill orchards and plantings on 

 rough lands are common, the stationary plant aids in solving the serious 

 problem of doing a thorough and timely spraying job. 



2. The necessity for hauling machines between closely planted trees 

 and those loaded with fmit is eliminated. 



3. Damage to cover crops or intercrops is reduced. 



4. The application of materials to the trees goes on without inter- 

 ruption. There is no time out for refilling. The amount of effective 

 work accomplished by a given crew of men is increased from 25 to 50 

 percent over the portable outfit. 



5. It releases teams, tractors, and the men to drive them, for other 

 forms of work. 



6. There is less wear and less depreciation on machinery in a fixed 

 location and on a solid foundation than on that hauled through the 

 orchard. Its period of service is therefore extended. Some plants have 

 given satisfactory service for 15 years. 



The chief advantage, already implied, is that it makes the 

 grower almost independent of soil or weather conditions, so far 

 as his spraying program is concerned. 



On small enterprises, especially where teams or tractors 

 are needed for other work and must be retained whether used 

 for spraying or not, it is probable that the portable oufit is 



