The Hood River glacier. (Hood River, Or.) 1889-1933, 1922-12-28
EXPERIMENT STATION
GIVES DRY ROT DATA

Editor Glacier: Some time ago there
appeared in your columns letter ask
ing for information concerning some OF
the orchard problems of the valley.
To adequately answer all of the ques-
tions we fear that much valuable space
in the newspaper would be employed.
perhaps to the impairment of the issue.
However, a number of the questions
asked are of much interest to many
growers in the valley and we are glad
to present such information on the sub
ject as is available.
1t is regrettable that all of the facts
which bring about dry rot and core rot
of apples are not known. These dis
eases are classified as physiological
troubles. there being no definite fungus
or insect organisms associated with
them. Troubles of this sort are irreg-
uiar in occurrence and must be traced
back to some unbalanced condition,
either in soil moisture, plant food or
perhaps something irregular within the
tree itself, probably induced by some
of the conditions already mentioned.
| Usually in extreme cases we find tree
| injury associated with these two
| troubles in the form of Dieback or so
called Rosettc. A we'll known Aus
tralian author on this subject has pre-
pared five volumes and has spent many
years investigating the cause, but in
| his conclusions he is unable to place
his finger upon the set of conditions
which bring about this trouble.
Under our conditions at least, we
can positively state that thorough
orchard practices, such as careful cul-
tivation and rotation with cover crops,
supplemented with uniform irrigation.
has in many instances corrected large
acreage severely affected by this con-
dition. However, there are many ex-
ceptions, and the trouble often cOntin-
ues to develop regularly despite the
| fact that growers have been very care
full with these practices. This prob
ably leads us to point below the sur
face of the ground, and it is quite
probable if we could picture a cross
section of this soil condition, that is,
the ground throughout the year with
reference to its dryness or its exces-
sive water condition, we would be sur
prised.
Many observations that we have
made lead us to believe that during
some parts of the year, and perhaps
for only short time, water has be-
come over-abundant, resulting in some
mechanical injury to the feeding roots
of the trees. We have made some OBJ
servations here at Hood River, with
reference to the water table in some |
orchards, and have found this very
high even on ground which would have |
the appearance of good drainage. 1t |
was probably due to this fact that dry |
rot and core rot developed, causing so
much damage in these orchards. In
one particular case as the water table
lowered. the dry rot diminished pro-
gressively until not present at all. 1t
would seem then, that growers should
more critically understand their soil
moisture and particularly the rise and
fall of their water table if they are ex-
periencing much trouble of this sort.
An examination should be made at def
mite intervals throughout the year, as
it would take regular observations, say
not to exceed every three or four
weeks to accurately determine this
water condition because of fluctuations
that occur during the season. We be-
ieve that drainage employed along
with the practices suggested would
reduce this trouble.
In next week s issue, we will discuss
water core.
Hood River Experiment Station.