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 1s 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: 
Damiex Gis lalke ds) fel. P72 SR eee Dee ee ee per barrel.. $1.75 
SUN (MONT oo = Soe oe ss ee ee Ree per 100 pounds. - 2. 65 
Caustic soda, in 120-pound cases...........----------per pound. - . 054 
Borax in dPnound cageses es iccths lt SSA LENE: | eee 1. 40 
Dive; tm: ASM tid CASS a fj cire co bie ve Leone ni yet eee epee ee 3. 25 
Bushwoull <mt loarrelelotis: says eee eee eres eee rere eye 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 
Commercial lime-sulphur solution .................--per barrel.. 410.00 
Commercial distilate-oi] emulsion...-...2i54..--.-..-!1-d0..2. sy. 50 
Commercial distillate emulsion and caustic soda... ......-.-do.... %9.95 
A good fish-oil soap can be made at the following cost: 
Tisje 2 SOUS a. ons te eee a ee ee noe ee $0. 1354 
Bish orl y-eallons 2 64. Atos doe ok ee ee oe et 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. 
Hish-oil'soap, 30: pounds... S25 3. Aces See eee $0. 495 
Distillate oil(28° /Baumé); 20 eallons 2. 3 ce. 5.) eee 1. 400 
POtalts 2 digs os eee tei eee 1. 895 
This makes $1.895 for 36 gallons, or $0.0526 per gallon. 
a About. 
