White Bluffs spokesman. [volume] (White Bluffs, Wash.) 1907-1938, 1926-01-08
SPRAY FOR SCALE

Or M rSN 0@o3G
In applying the dormant spray for
scale there are three very important
factors to consider.
The first, and most important of
of these factors, is very thorough
It necessitates that the
spray hit each insect in order to kill
it. A scale. is many times smaller than
a head of pin, and in many cases.
the insects are pretty well scattered
over the tree. If two or three small
scaley twigs are missed or poorly
sprayed, there is an ample number of
scales left to infest the remaining
tree by the end of the season. To APP
ply a thorough application of spray
the machine should be in first-class
condition. A pressure of at least $50
pounds should be obtained through
disks with 1-8 of an inch hole. If
pressure between 300 and 400
pounds can be obtained SO much the
better. The tree should also be pro-
perly pruned to permit the free en-
trance of spray.
The second factor is the time of ap-
plication. Many growers have been
spraying too late. The scale is the
weakest just before the sap starts to
flow in the spring. After the sap
starts to flow, at which time they are
about half grown, the scale starts to
feed and recuperate. The longer they
feed the more vigorous they become
and the harder to kill. The most sue
cessful spraying is done before the
green shows from the buds.
There are two scale sprays in use
in this district. These are the oil
emulsion sprays and lir1e-sulphur
solution.
The oil sprays will in time be a
better dormant spray than lime-sul-
phur. It has given better control Of
orchard insects than lime-sulphur in
most all of the experiments that have
been carried on. In orchard practice,
lime sulphur has given the best re-
suits, due mostly to two reasons. The
main reason is the unstable oil used.
This is no ones fault in particular.
The oil companies have not been given
well-defined specifications to follow
and are not rssonsible for any unstable
oil used. The only instruction which
we have in this regard is from DIR.
A. L. Melander of the State College.
He quotes, "For dormant spraying the
oils that gave the best results in the
experiments of 1924 were the so-cal,ed
neutral type of lubricating oil. Heavier
oils apparently lack penetration and
lighter oils do not have body enough"
Even in the experimental work this
difference has been noticed and out ir
the. orchards where the spray is not SC
thoroughly mixed this difference is
more noticeable. There is no prac'
i teal way to test the oils to see if sucl
stock has been adulterated and nothing
more than an approximate standard OF
specification has been worked out.
The second reason is the carless
ness on the growers part. For some
reason or another, which cause has no
been definitely determined grower
is worse off to spray carlessly will
oil than he is to spray carelessly will
line-sulphur. It takes more skill ans
more thorough spraying on the grow
er's part to use oil.
Lirne-sulphur is the standard ane
we'll established scale spray. The dis
agreeableness of. its application, ant
possibly to getl.a little cheaper spray
are the only reason that we shoul
seek another spray. Its results hav
been very satisfactory, where thor
ough job Of spraying has been done
Due to the above mentioned result
of the use of oil, and due to the neces
sity Of spraying with lime-sulphur fo
blister mite and peach twig boreJ,
recommend that all growers spra,
J with lime-sulphur this coming season
A preference should be given the liqui
concentrate. It is the most compatibl
and consistent. In all cases see tina
: the solution tests at least degree
Brurne in the tank. Rely on the hydro
meter rather than the company recon-
mendations for the amount of spra
used. The hydrometer only costs
dollar. In conclusion wish to en-
! phasize that it takes thorough 10
) of spraying with proper strength {
solution to give satisfactory contrs
of scale. It is well established fac
, that the grower may be using falls
: economy to spray with less than
4 per cent solution of lime-sulphur
E. E. Hill. District Horticulturist