Lewiston evening teller. [volume] (Lewiston, Idaho) 1903-1911, 1908-04-25
LIME-SULPHUR SPRAY FOR THE
SCAB,
A. B. Cordley, Entomologist, Oregon
Experiment Station.

that some means be found of re-
ducing the injury. or that some
| spray be discovered that may be
used as substitetu for the Bor-
deaux mixture.
For the past two or three years
l have observed after winterspray-
ing apple and pear trees with lime
SULPHUR solutions. for San Jose
scale, that the fruit upon the spray
ed trees was less 'scabby' than
that upon unsprawed trees Upon
| two different occasions this winter
duplication was delayed until the
| blossoms were about to open, and
while the spray which, was applied
at the full strength did considerable
| injury at the time, its decidedly
| beneficial effects We're noticeable
when the fruit was gathered.
However, the generally good results
which follow winter applications
of lime-sulphur are now well known
and this part of the work requires
no further comment.
Nevertheless, these observations
/ suggested to me the probability
that lime-sulphur solution might be
used as a substitute for Bordeaux
mixture for summer applications,
and during the past year I have so
used it upon various plants and for
various purposes.
| Some of the results obtained
show conclusively that lime-sulphur
applications may used as a summer
spray without injury to foliage and
also point strongly to the probabil'-
ty that by its use apple scab may be
effectua'ly controlled without dan
ger of spray injury to the fruit.
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 single seasons
work point so strongly to this con-
clusion that feel justified in call
ing attention to them, that growers
| who have suffered loss from Bor-
deaux 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 solu-
ton could be used without injury
to the foliage. This, again, made 1t
necessary to adopt some system OF
standard ling" the spray. After
considerable work we adopted what
may be called the "stock solution"
method of preparing the spray and
, adopted for the standard of the
work "stock solution" having
specific gravity of 1.27 Cor de-
terming the specific gravity of the
solution while at work in the field,
we have found the specific gravity
hydrometer, a very convenient in
strument, It is cheap, simple and
convenient. and would recommend
| every grower who expects to use
lime-sulphur as 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 COL
or, Is without sediment, and as we
stated above had specific gravity
of 1.27 Analysis showing that
each gallon contained 2.3S pounds
of sulphur.
During the season Of 1907 these
'stock solutions" of lime-sulphur
were used variously diluted upon
the apple, pear, peach, plum, prune,
ounce, cherry, grape, potatoes and
ce'ery.
The results obtained indicated
that lime-sulphur sprays produced
by diluting one gallon of the stock
solution with Is gallons of water
may be safely used upon all of the
above named plants with the ex-
ception of the peach unless it may
be early in the spring when very
slight injury is produced For use
upon the peach each gallon of the
solution should be diluted with at
| least 20 gallons of water.
For the experiments with apple
scab block of 400 Yellow New
ton trees were selected, because this
| variety is particularly susceptible
to the disease and because this
block was known to be badly eff
fected.
The entire orchard was sprayed
with lime-sulphur for San Jose
scale late in February The orch
ard was then divided into two plats
| One plat was sprayed with Bor-
deaux on April 90, May and MAY
! II. The other plat was sprayed on
the same dates with the lime-sul-
phur solution diluted lis. Tn
sprayed trees were left as checks in
each plat.
At picking time the fruit was
carefully gathered. examined and
seDarated into three grades to show
fruit absolutely free from seab