The Hood River glacier. (Hood River, Or.) 1889-1933, 1905-02-09

Courtesy Pacific TIo"o"stead.l MT. HC
1t seemed, however, that the great
est injury was done by the first ap-
plication, as those trees sprayed lost
nearly as many leaves as the ones
treated three times.
Two rows adjacent to the paris green
treated trees were sprayed at the same
time with arsenate of lead, prepared
at the time of application, and used
at the rate of pound to 300 gallons,
figuring on the actual dry weight of
dry arsenate, No lime was used and
no injury developed. The trees we're
yellow Newtown pippins.
The third spraying experiment was
conducted on White Winter Pear
mains and yellow Newtowns. Asenite
lime was used This compound is
close relative to the Kedzie mixture,
the difference being that sodium ars-
enate instead of sodium arsenite is
used in its preparation.
The formula Of the first application
was: Arsenate of soda, l3 ounces,
lime 6 pounds, and linseed oil pints,
with 100 gallons Of water In the sec
ond application no oil was used and
the water was increased to l75 gal
Ions and the lime to s pounds.
The third application was the same
as the second. No injury to the foli-
age was noted until after the third
when there was some spot
ting and yellowing Of the leaves of
the Yellow NpwtOWnS
After the hot spell considerable
number of leaves yellowed and fell
from the Newtown trees and slight
injury to the Pearmains was noted.
The principal experiments were sup
plemented by many others, in which
varying quantities of the ingredients
were tested, and also various substan-
ces not commonly used in spraying
were tried.
In no case was paris green used on
NeWtown foliage without injury
more or loss marked before the close
of the summer. Arsenate and ars-
enite of liUe we're also used in con
which would be effective
against the Goblin moth. Arsenite of
lead was also found to be quite injur-
ious.
Arsenate of lead, however, proved
very safe. aud the commercial brand
known as Disparene was entirely
Swift's arsenate of lead was slightly
injurious to peach foliage when used
in excessive quantities, but the am
cunt required for the control of the
Goblin moth had no injurious effect.
Experiments with home made arse
nate of lead showed it to be somewhat
more injurious than Swift's, although
no injury was noticed in the spraying
work on the Yellow Newtowns.
In making a choice between these
it is desirable to get the
greatest control of the moth with the
least injury to the tree possible.
Apple counts were made with all the
experiments and the percent
age Of wormy fruit taken.
With the lead arsenate the wormies
averaged l3 per cent, and the adioin-
ing row of oil paris green, l6 per cent
Checks in this part of the orchard ran
40 per cent.
In another part of the oarchard oil
and paris green spraying averaged "a
per cent Wormy, while corresponding
checks were 70 percent.
The arsenate of lime spraying ran 36
per cent wOrmy for White Winter Pear
mains and 81 per cent for yellow New
towns.
These figures do not show as good a
control as can be had by spraying, for
last years experience showed that a
95 per cent control was easily attain
able in the valley orchards.
In this years experiments the first
was not applied until June
Dist which allowed the first brood of
worms to mature without check. This
meant large second brood to con
tend with. Then the number of ap-
pies on the greater part Of the trees
was small, which had the effect of
raising the per cent of wormies.
Aside from the field Of work large
amount of time was spent in the labo
ratory, chiefly with chemical analysis
Of leaves taken from sprayed trees and
in killing experiments to determine
the insecticidal properties of various
A fuller statement of the
laboratory work viii appear later
The object of the analysis was to
the condition and the
amount of arsenic to be used
As a result of the study of PajaTo
valley conditions for two seasons we
are not able to recommend paris green
for general spraying. The same may
be said Of the KedZie mixture or the
Taft formula. In fact, the only spray
which has combined good killing pro |
perties with neutral behavior towards |
foliage Is arsenate of lead.
Lead arsenate will be somewhat |
more expensive than any other pre-.
but if it does the work this |
point will not be vital objection. |
With arsenate of lead spraying can
be done at any time through the sea
son. This is very important, as the
control of the Goblin moth will de- |
Band an almost incessant treatment |
from the opening of the blossoms to
the picking of the fruit.
The important brands of CONNER
rial asrenate of lead have been in
vestigated, and we have decided to re-
commend Swift arsenate of lead for
use next year. Disparene has so far
proved less effective, but it is not de-
sired to pass definately on il until
further trials have been made.
The comparison Of home made lead
arsanate with the coomemrcial brands,