a ee 
7 
against scale insects for twenty years. The distillate emulsion gener- 
ally employed in California for spraying citrus trees, on which the lime, 
sulphur, and salt wash can not be used, is substantially the same thing, 
except that it is made with the California distillate or petroleum oil. 
Crude petroleum of any kind, as well as the refined product, may also 
be used in making thisemulsion. The use of the soap emulsion against 
the San Jose scale in the East has not been very general on account of 
the greater facility with which the pure oil or oil-water mixtures can 
be applied. The difficulty of obtaining uniform results with the latter 
has led to a return to the use of emulsions to some extent, and there 
can be no doubt about their superior merit when it is desired to dilute 
the pure oils. Emulsions may be applied atany strength with absolute 
confidence that there will be no variation. Where the emulsion can be 
prepared wholesale by steam power, its employment is attended with 
no difficulties. In California it is prepared by oil companies and sold 
at very slightly more than the cost of the oil and soap ingredients. It 
is made after the following formula: 
IPEUROIGWTIN SE 6 eae oa ee eee enn yrs Oa gallons.- 2 
Wanale-olisoapy (or I quart soft soap) 22-222. J22222--22- eee pound... 3 
Wy enuere: (Stove) oo Ske et ee lps ee ee Reem LOD rh i | | gallon.. 1 
The soap, first finely divided, is dissolved in the water by boiling 
and immediately added boiling hot, away from the fire, to the oil. The 
whole mixture is then agitated violently while hot by being pumped 
back upon itself with a force pump and direct discharge nozzle throw- 
ing a strong stream, preferably one-eighth inch in diameter. After 
from three to five minutes’ pumping the emulsion should be perfect, 
and the mixture will have increased from one-third to one-half in bulk 
and assumed the consistency of cream. Well made, the emulsion will 
keep indefinitely and should be diluted only as wanted for use. 
In limestone regions, or where the water is very hard, some of the 
soap will combine with the lime or magnesia in the water, and more 
or less of the oil will be freed, especially when the emulsion is diluted. 
Before use, such water should be broken with lye, or rain water should 
be employed. 
For winter sprays dilute the emulsion with either 3, 4, or 5 parts of 
water, giving a percentage of oil of approximately 17, 13, and 11 per 
cent. The strength in oil of this application on trees as compared 
with the oil-water sprays is the equivalent of 25, 20, and 15 per cent 
oil, because relatively more of the heavier oil-soap emulsion ts held 
by the bark. The two stronger mixtures may be used on the apple 
and pear and the weaker one on peach and plum. 
For summer applications dilute with 7, 10, or 15 parts of water, 
giving approximately 8, 6, and 4 percent of oil. The weaker strengths 
may be used on trees with tender foliage, such as that of peach, and 
the greater strength for strong foliage plants, like the apple and pear. 
