PLANTS AND ANIMAL PARASITES 165 



is very useful for greenhouses and grounds. The size 

 and number of the phmts to be sprayed will largely deter- 

 mine the kind of spray apparatus to be used. The 

 atomizer and knapsack pump are adapted only to rather 

 small plants when they are few in number. In the home 

 or small commercial orchard hand pumps may be used. 

 Sometimes a portable outfit is made by mounting a 



Fig. 71. Fig. 72. 



Fig. 71. — Barrel pump for small orchard. 

 Fig. 72. — A good spray outfit for a garden or a plantation of low trees. 



barrel on wheels, as in Fig. 72. There are two general 

 types now on the market : one in which the handle 

 works vertically (Fig. 71), and in the other horizon- 

 tally. The latter is more expensive, but is adapted 

 to larger orchards and is easier of operation. For 

 large commercial orchards power pumps, usually oper- 

 ated with compressed gases or with gasoline (Fig. 73), 

 are most economical and efficient. If good work is to 

 be done in spraying trees, a rod to elevate the nozzle into 



