62 INSECT PESTS OF FARM, GARDEN AND ORCHARD 



readily repaired, has no agitator, and requires frequent pumping. 



On the other hand, they are easily carried, do not leak, and 



leave both hands free, so that 



one might be used for spraying 



a small tree from a step-ladder. 



These compressed-air sprayers 



cost from $8 to $20. 



Barrel Pumps. The most ser- 

 viceable spray pump for the 



average farm is the barrel pump. 



With a good barrel pump 100 to 



150 full-grown apple trees may be 



sprayed in a day, so that it will 



be found sufficient for an orchard 



of 500 trees or less. By using a 



row-spraying attachment, a few 



acres of potatoes or other row 



crops may be sprayed with a 



barrel, pump much more quickly 



than by hand. In buying a row 



attachment, be sure that it is ad- 

 justable for rows of different 



widths. A good barrel pump costs from $25 to $50. Most of 



the pumps sold for less are too light to do effective work or 



n= _ =^ are not well con- 



-' structed, Numerous 

 pump companies ad- 

 vertise in the agricul- 

 tural papers and after 

 considering the follow- 

 ing points one may 

 || select a suitable pump 

 from their catalogs: 



1. The pump should 

 be guaranteed to fur- 

 nish two nozzles at 80 

 to 100 pounds' pressure 



Fia. 31.-The knapsack sprayer in use. th Ordinar y 



(Spramotor Co.) ing. 



FIG. 30. One of the best types of 

 knapsack sprayers. Note foot- 

 rest, agitator, handle, and wide 

 straps. (Deming Co.) 



