
20 
Later studies of the action of this wash in California led the writer 
in 1900 to give it a further careful trial in the East, with most suc- 
cessful results, demonstrating that, with favoring conditions, i. e., 
absence of dashing rains for a few days after the application, it would 
give just as good results in the Eastern States as on the Pacific coast. 
A year later (1901-2) very elaborate tests conducted by Doctor 
Forbes in Illinois showed that fairly hard rains-will not always in- 
validate spraying with this mixture. A vast amount of experience 
of the most practical kind since gained, contributed to by all the 
eastern experiment stations and by the big commercial fruit growers 
of the Middle and Eastern States, has fully demonstrated the prac- 
tical merit of this wash and its superiority to others in point of safety 
to trees and in cheapness. Its disadvantages are the difficulty of 
preparation and the heavy wear whicn it entails on apparatus—objec- 
tions, however, which do not offset its notable advantages, particu- 
larly for commercial orchard work or where the number of trees to 
be treated is sufficient to warrant the trouble of its preparation. It 
is, in fact, the standard spray now used in commercial orchards for 
the San Jose scale. 
Composition and preparation.—In the matter of composition of the 
wash, scarcely any two experimenters agree. Salt was a part of the - 
original composition of the sheep dip and has long been retained, 
with the idea that it added, perhaps, to the caustic qualities, and par- 
ticularly to the adhesiveness of the wash. For the latter purpose a 
very small amount only, 1 or 2 pounds to the bushel of lime, need be 
added, following the custom in the preparation of whitewash mix- 
tures. In practical experience, however, the salt seems to have been 
of very little benefit and is therefore omitted in the formula now 
given. The proportion of lime and sulphur is a matter of some in- 
difference. The mixture obtained is sulphide of lime, and if an ex- 
cess of lime is used it simply remains undissolved in the mixture and 
adds to the whitewashing character of the application. Too much 
lime is distinctly objectionable, however, because of the greater difli- 
culty of spraying and harder wear on the pump and nozzles. The 
formula here given is substantially the one which has been hitherto 
recommended by this Bureau, reduced to the 45 or 50 gallon basis, or 
the capacity of the ordinary kerosene barrel commonly used in its 
preparation by the steam method. 
ROT SLCC LIGA! SL Le Thee BEE ee pounds__ 20 
lowers O17 Sulphunet ats assy eee eet oe oh 15 
NAVEEN ety "UC0) NEUE fel lee es See Ae SIONS ee Se See ea gallons__ 45 to 50 
The flowers of sulphur, although requiring somewhat longer cook- 
ing, seems to make a better wash than ground sulphur, but the latter 
may be employed. Stone lime of good quality should be secured and 
127 
