The Delta independent., 1922-08-04
CALIFORNIA PEACH SPOT
OR coRYNEUM BLIGHT

OR coRYNEUM BLIGHT
California peach spot, otherwise
known as Coryneum blight or spot
winter blight, brown spot (not brown
rot) fruit spot, postular spot, ha.
made it's appearance in Colorado
peach orchards in serious amounts
within the last few years. Mesa ant
Delta county peach growers reported
loss last year ranging up to TWEEN
ty-five per cent of the entire crop
loss to this years crop due to the
disease that would hold over to in
feet this seasons twig growth and
fruit With a large crop over the
| country only high grade fruit can be
expected to bring satisfactory re.
turns.
This fungous disease attacks the
fruit, buds, twigs, and leaves. On
the fruit a developed spot looks very
much like San Jose scale. On first
appearance, the affected area is a
dark or purplish red. Later a light
spot develops in the center. On the
bark, at first, the appearance is very
much as on the fruit. Later, how
ever, slit may be formed and gum
ming is likely to occur. In our state,
the most serious damage, beside the
spotting Of the fruit, is caused by the
killing of the fruit and leaf buds
This disease kills the surrounding
bark as well as the buds, very often
girdling and killing the twig beyond
the diseased buds, thereby seriously
cutting down next years crop. On
the leaves the spots have the charac-
teristic red circle around a grayish
brown center. These spots may, or
may not, fall out.
Delta county peach growers. who
have sprayed for this disease several
seasons, have obtained satisfactory
control by spraying with self-boiled
Lime-sulphur Just as the fungus
makes its appearance on the fruit
The spots spread very rapidly once
they start, so close watch should be
kept after the middle Of July, or
sooner il the showers begin before
that time. Besides the application
of self-boiled Lime-sulphur as the
spot begins to appear, it will very
likely be profitable, il the disease is
serious, to apply another spray soon
after the fruit is picked. For this
second spray Bordeaux mixture is
usually preferred. After the disease
is we'll under control, this early fall
spray of Bordeaux mixture will prob
oh ha g,,fE Ddranffnnc
making the above sprays can be OBJ
tanned by writing the State Depart.
ment of Horticulture. Grand Junction.
A pamphlet discussing this disease in
detail may be procured from the
same address.
In case commercial sulphur cannot
be obtained locally. the following
Denver firms have been recommend
ed: L. A. Watkins, Merchandise Co.
1915 wazee; Denver Fire Clay Co...
Brothers Drug Co.
While the above recommendations
are not based on careful experiment
tai work in Colorado. they are based
on the practical experience Of Colo
RADIO peach growers, the writer's OBJ
servations in Colorado orchards. and
experiments in other states. AS u.s.
ual, thoroughness and the correct
spray at the right time are the most
important items In the successful con-
troll of this disease. Cover every
peach, leaf and twig with especial at
tention to the fruit growing in the
lower half of the tree. Watch your
fruit for spots. While this disease
may not have been serious In your
orchard last year. 1t spreads rapidly
under favorable (shower) conditions.
Don't let your seasons work be lost
by omitting this spray.-H. D. Lock
lin, State Dept. Horticulture