Insects of Shade Trees and Their Control. 29 
Extra parts Extra parts of the equipment most subject to wear 
or breakage should always be on hand. Failure to observe this pre- 
caution will frequently result in delays at critical spraying periods. 
Tools.—Tools specially made for the different parts of the spray- 
ing outfit are usually supplied by the manufacturer. Other stand- 
ard tools, however, such as wrenches, screw drivers, hammers, etc., 
should be carried in the tool box in case of need. 
Help.—tIn solid-stream power spraying at least 5 men are required: 
One mechanic and driver (or chauffeur if the outfit is mounted on a 
power truck), three men at the hose, and one at the nozzle. If more 
than 150 feet of hose are used, more men will be needed. 
It is perhaps not out of place to state here that, in view of the 
fact that spraying is practically futile unless it is intelligently done, 
it is not only desirable to have the help in this work intelligent and 
measurably well informed, but also to have the rewards of their labor 
sufficiently attractive to hold them to a certain degree of permanence, 
thereby insuring etfectiveness and efficiency. In the long run such 
a policy will prove the cheapest and 
most satisfactory. 
SPRAY DILUTION TABLE FOR 
READY REFERENCE." 
Table I shows the amount of spray 
material required for a number of 
different quantities of spray. The 
rate at which the materials have been 
computed will be found in the first 
column. The figures at the top of the 
table represent the total number of 
gallons of diluted spray desired, and 
the figures in the vertical columns "6. 16.—Strainer for use in re- 
3 : moving sediment in sprays when 
give the amount of spray material these are being poured into the 
required. Thus, if 150 gallons of San nk. (Quaintance and 
arsenate of lead, paste, at the rate of iy 
2 pounds to 50 gallons, is to be used, it will be noted in the table that 
6 pounds is required. Again, if 100 gallons of kerosene emulsion, 10 
per cent strength, is wanted and the stock solution contains 66 per 
cent of kerosene, it will be found by referring to the table that 15_ 
gallons of the stock emulsion should be used. 
u Adapted from Farmers’ Bulletin 908. 
