158 DECIDUOUS FRUIT INSECTS AND INSECTICIDES. 
results to use a power outfit at a high pressure and a coarse drenching 
spray to penetrate the lichens and the heavy scale incrustation. A 
power sprayer is especially useful in applying distillate-oil emulsion, 
crude-oil emulsion, and mechanical mixtures of either, as a hand outfit 
does not give sufficient agitation for a perfect emulsion. 
The writer recently noticed several prune orchards which had been 
sprayed with a commercial distillate spray and caustic soda at 4 per 
cent strength; they were well cleaned of the scales and lichens. 
COST OF SPRAYING. 
Table IV shows the comparative cost of materials of the most im- 
portant and efficient treatments. To get the total cost of spraying 
it will be necessary merely to add the cost of the labor, which is vari- 
able and was therefore not included. Usually 3 men and a team 
are required for spraying with a hand pump and the same number 
with a power outfit, adding an additional man and team where a 
supply wagon is used. 
The number of trees that can be sprayed in a day is variable, 
depending upon the size of the trees, the availability of the water, and 
the efficiency of the labor. With medium-sized prune trees, from 800 
to 1,000 trees is considered a good day’s work with a power outfit 
and a supply tank. 
Below is shown what the ingredients of the spray mixtures would 
cost the fruit grower in the vicinity of San Jose in barrel lots: 
bevanteat Litt y Cro) Regs ee Ae ES ee ae ee per barrel... $1.75 
SUL POUTMHOUN) cuenta £6 -= - hehe eb bse per LOO pounds. . 2. 65 
Caustic soda, in 120-pound cases.............-.------per pound. . . 054 
Doras, id2-pound ‘cases. 4h. ole ee ee. es see ee oe 1. 40 
Lye im t8-pound Cased: 2.ge ...\ieiss| ie. anes 2 ae Se cee eee 3. 25 
[Erts)icroytl Eerrtynie] og-perrel lel Woy Pwep eye ara Sena he SLC eh) oe per gallon. . . 30 
Crude oil (12 to 24° Baumé), in 110-gallon drums.................- 3. 00 
Distillate oil (28° Baumé), in 110-gallon drums ....... per gallon. . . 07-. 09 
Jommercial lime-sulphur solution ........-....-.---- per barrel.. 10.00 
Commercial distillate-oil emulsion..............-...----.-- doss-= ) Cx/a0 
Commercial distillate emulsion and caustic soda............do.... %9.95 
A good fish-oil soap can be made at the following cost: 
Lyey2) Poumdsind 4. fietias. tee da ee 4 se Lae eee ee -oeeeeeeee 30. 1354 
Bish oil: Mata one eeete sheet terete he erase torn ae eee ee . 5250 
Water, 6 gallons. 
This makes $0.6604 for 40 pounds of soap, or $0.0165 per pound. 
The concentrated distillate-oil emulsion (55 per cent) will cost: 
Hot water, 12 gallons. 
Fish-ol soap, cO POmNdss, -.50 + ark kets ste hee te ane eee eee $0. 495 
Distillateroili(2ss Banme)s20loalllonseecns seers See: eee 1. 400 
Motel syed ayrcind a Geed fs iets dee oe Bee ated. eee sees 1. 895 
This makes $1.895 for 36 gallons, or $0.0526 per gallon. 
@ About. 
