The Topeka state journal. [volume] (Topeka, Kansas) 1892-1980, 1915-12-04

cases, then three or four days t. a
week later with a gouge or sharp
knife retrim the margins to make
sure that you worked beyond the
blight at all points. The bark will
discolor naturally, so that this blight
can not be detected without retrifn-
ming. If any of the blight were left it
is thus given an opportunity to dis
color further the bark and show itself.
/ This works better in warm weather
than in cold weather
Having cleaned up the blight thor
oughly in the fall, when dealing with
bad outbreaks it is a good plan to go
over the orchard tree by tree and in
spect in early spring when the buds
are swelling, but well ahead of the
blossoming period, TO make sure that
no cases escaped. A bit of gummy
eXudate will, of course, immediately
lead to examination with a knife and
gouge. Carry the kit of tools and dis
infect and be prepared for further
work on such cases. Occasionally a
Notwithstanding case may be par
TALLY or completely retrimmed, as
above suggested.
Painting Wounds.
In the autumn, after the wounds or
eradication scars are made, disinfected
and perhaps reinspected when deemed
necessary, the exposed area of wood,
especially if one inch or more in di-
ameter, should be painted for protec-
ton, as in case of pruning and other
wounds. Since many of these areas
may be large, it is important to give
this wound treatment. Various ma
terials are availa BILE, such as white lead
paint, liquid grating wax, coal tar, or
a mixture of three-fourths to two
thirds coal tar and one-fourth to one
third creosote oil, all to be applied
with a stiff brush. Liquid grating
wax is somewhat expensive and often
requires warming, so that it is not
usually preferred. Coal tar, while
cheap, requires warming, and is there
fore difficult to apply. The depart
pose mainly white lead paint (made
rather thick, and preferably given a
second coaO or the coal-tar creosote
mixture.
Whitehead paint has some advan-
tageS. 1t is readily obtained and ap-
piled, and if any of the gummy exu-
date, which is more or less reddish or
brownish in color, flows from an inn
perfectly worked case, it is readily de-
tected on the white surface. On the
other hand, this paint has proven a
disappointment to the department and
experiment station pathologistS in that
it frequently has not preserved the
wood from decay. 1t is rather too
mild disinfectant The wood cracks,
let's in water and fungus spores, and
frequently after three or four years
and before large wounds have healed
wood-rot fungi have entered and de-
cayed the wood under the paint. Even
though applied to the wounds when
they are dry, the sap pressure, even in
the autumn, often lifts the paint from
the surface of the wound, particularly
in the case of scars on the ends of the
branches.
The coal-tar cresOs Ote-oil mixture is
not open to these objections and for
these reasons is rather preferable. 1t
is used very commonly and successful
ly on shade trees, and while there is
still some question about it's use on
fruit trees, it has given good results
on pears and apples, even though the
healing from the margin does not pro-
coed quite as rapidly and smoothly as
with the lead paint The coal-tar
creosote-oil mixture is a powerful dis
infectant and waterproof coating. If
made too thin it penetrates rather too
deeply and does not answer fully for
waterproofing. If made too thick 1t
is not convenient to apply. In cold
weather slight warming is sometimes
useful, but with a stiff brush under
ordinary conditions it works well. 1t
has a tendency to kill the wood under
the cambium slightly and sometimes
to kill back a little, BIT it does not
kill the edges of the bark to any ser
ious extent. This mixture is best ap-
piled imm ediately after making the cut
or at any rate as soon as possible after
inspecting the wounds. 1t sticks well
even though the cut surface on the
end of a branch is still somewhat
Pear blight eradication is quite a
careful piece of work. 1t requires
close attention on the part of the or
chardiSt or careful training of the help
who may be engaged in it. Remem-
Der that thoroughness is essential for
success. 1t is not necessary to deter
mine in all cases whether the blight is
alive or dead on the lower margin. al
though somewhat helpful a guide in
determining how low to go. In actual
practice it is better to cut out all the
dead limbs and all the blight anyhow,
regardless of whether it is dead case
or not.
The blight eradication should always
precede the pruning. Other pruning
for shaping up the trees may be done,
if preferred, before leaving the trees.
venient time later. but of course, be-
fore the buds push in the spring
Apple Cankers.
Apple cankers form dead spots on
the twigs and branches of apple trees
and occasionally extend down on to
the bodies. There are several differ |
ent types of apple cankers in various
parts of the United States. Occasion |
ally two or more kinds may occur on !
fungi growing comparatively slowly in |
the bark and killing it. They often /
enter in the twigs, fruit spurs. OF
areas killed by pear blight, |
but may infect entirely independent of /
these sources. Frequently locust |
scars, pruning wounds, or other in |
juries furnish the point of entry, but |
some kinds of cankers infect directly |
into the bark.
The blister canker common in the /
middle west. is particularly severe |
after winter killing or after the trees /