Heppner gazette. [volume] (Heppner, Morrow County, Or.) 1892-1912, 1908-04-02
THE LIME.sULPHUR SPRAY.
Good Preventive for Apple Scab and
Less Harmful Than Some.

The serious results in the form OF
Bordeaux Injury" which often follow
applications of Bordeaux mixture rem
der it almost imperative that some
means be found of reducing this injury,
or that some spray be discovered which
may be used as a substitute for Bor-
deaux.
For the past two or three years have
observed, after winter spraying apple
and pear trees with lime-sulphur solu-
tons, for San Jose scale, that the fruit
upon the sprayed trees was less "scab.
by'' than that upon .unsprayed trees.
Upon two different occasions this winter
application was delayed until the bios
SONS were about to open and while the
spray, which was applied at the full
strength, did considerable injury at the
time, it's decidedly beneficial effects
were noticeable when the fruit was
gathered. However the generally good
results which follow winter applica.
tions OF lime-sulphur are now well
known and this part of the work re-
quires no further comment.
Nevertheless, these observations sug.
gested to me the probability that lime
sui . hur solution might be used as a
substitute for Bordeaux mixture for
summer applications and during the
past year have so used it upon vari-
GUS plants for various purposes.
1t is not proposed at this time to go
at all into detail regarding these ex.
periments-I wish only to call atten-
tion to some of the results obtained
which show conclusively that lime
sulphur solutions may be used as a
summer spray without injury to foliage
and also point strongly to the probabil-
ity that by it's use apple scab may be
effectually controlled without danger OF
spray injury to the frnit.
Sufficient work has not been done to
Justify the statement that lime.sulphur
is equal to Bordeaux as preventive OF
this disease but the results of the single
seasons work point 60 strongly to this
conclusion that feel justified in call
ing attention to them, that growers
who have suffered loss from Bordeaux
injury, and others who are interested,
may make comparative tests OF the two
sprays the coming season.
In carrying out the work the past
season it became necessary first of all
to determine how strong a solution
could be used without injury to the
foliage. This, again, made it necessary
to adopt some method of "standardiz-
ing" the spray. After considera BILE
work we adopted what may be termed
the "stock solution" method Of prepar-
ing the spray and adopted as a stand
ard for the work a "stock solution
having a specific gravity of 1.27. (For
determining the specific gravity of the
solution while at work in the field we
have found the specific gravity hydro
meter very convenient instrument.
1t is cheap, simple and convenient,
and we would recommend every grower
who expects to use lime-sulphur as a
summer spray to obtain one.)
This solution, similar to the Rex.
Niagara and Phoenix lime-sulphur
sprays upon the market, any of which
would undoubtedly do as we'll, is OF a
clear, dark amber color, is without sed-
iment, and as stated above had spe-
cific gravity OF 1.27. Analysis showed
that each gallon contained in solution
238 pounds of sulphur.
During the season of 1907 these
"stock solutions of lime-sulphur were
used varously diluted upon the apple,
pear, peach, plum, prune, ounce,
cherry. grape, potatoes and celery.
The results obtained indicated that
lime-sulphur sprays produced by di-
luting l gallon of the stock solution
with Is gallons of water may be safely
used upon all of the above-named
plants, with the exception of the peach,
unless it may be early in the spring,
when very slight injury was produced.
For use upon the peach each gallon OF
solution should be diluted with at least
20 gallons of water.
For the experiments with apple scab
a block of 400 Yellow Newtown trees
were selected, because this variety is
particularly susceptible to this disease
and because this block was known to
be badly infested.
The entire orchard was sprayed with
Iime.sulphur for San Jose scale late
in February. The orchard was then
divided into two plats. One plat was
sprayed with Bordeaux mixture on
Apirl 20, May and May II. The
other plat was sprayed on the same
dates with lime sulphur solution di-
luted LIS. Unsprayed trees were left
as checks in each plat.
At picking time the fruit was care
fully gathered, examined and separated
into three grades to show per cent of
fruit absolutely free from scab, slightly
scabby and badly scabbed. 1t was
then regarded to show per cent of fruit
injured by spray.
The summing of results is shown
graphically in the following table.
Column marked A shows per cent Of
fruit free from scab; B, that showing
only small scab spots; G, that badly
scabbed and unmarketable; d shows
spray injury.
A B G d
Unsprayed -. 1919 2s.7 5l.S c
Bordeaux .49.1 35.4 1916 31.9
Lime-sulphur. 1913 1873 5.S
1t must be remembered in interpret
;oo tbasa rosults that fhey reoresent