The Yakima herald. [volume] (North Yakima, W.T. [Wash.]) 1889-1914, 1911-12-27
State College Horticulturist Will
ing to Experiment in
Orchard Heating
FATAL TEMPERATURES
ARE NOT ARBITRARY
All Sorts of Fruits Last Spring
Lived Through Cold Supposed
to Be Too Severe-Peaches
Survived Pears

ugntlng IN the Yakima orchards may
be made this spring by Prof Morris
of the department of horticulture of
the state college. Prof. Morris is
anxious to get data from orchardists
who have used pots and to arrange
for tests. with records kept, and re-
suits compiled, in which different
sorts OF heating devices are used. The
state colleges of Oregon, California.
Colorado and other sections in which
valuable crops are menaced by late
spring or early fall frosts have car
ried on such experiments In the or
chards and undoubtedly similar ex-
periments in the Washington orchards
would be productive of information
important for the fruit growers.
Cold Lasted Long
Fire pots were used to a consider
able extent in the Yakima valley last
year, oil being the commonest fuel.
but the cold spell was so severe and
of such duration that many orchard
lists were caught insufficietly supplied
with oil. so that, while some believe
they proved the worth of the artificial
heating devices, others feel that they
did not have fair chance to try out
the frost fighting methods.
About Frost
Frost may be looked for when the
Temperature. as reported by the sta
tons OF the weather bureau, falls to
point or 10 degrees above freez-
ing Frost Is formed on surfaces
which are at freezing or below freez-
Ing A clear, cloudless and compare
lively calm night is also favorable for
frost. Clouds retard radiation or loss
Of heat from plants and act as a
screen to prevent the heat collected
from the SUMS rays during the day
from escaping into the upper air.
Moisture, when considerable eleva-
ton above the earth, is condensed in
to clouds; when the process of con-
densatlon is more active and the
Temperature of the air Is above freez-
Ing rain falls: when the temperature
Is below freezing, snow Is produced.
When the moisture of the air In i'm
mediate contact with the earth is
| condensed at temperatures above
freezing. dew is formed; when at
temperatures below freezing. frost is
deposited.
A severe frost about the end of
December. 1895. caused great dam
age to the orange crop in the River
side section of California, and started
the frost lighting campaign. 1t is a
good idea, according to the report of
the Oregon state college on prelimi-
nary frost fighting studies In the
Rogue River valley, for every or
chardist to make practice of keep
nj nj INN tAt,
WE'LL as the dew point for every day
Throughout the season. This will
give him data to go by for his par
ticular location and it has been found
that arbitrary rules and temperatures
cannot be given for different locali-
ties, Each fruit grower will find il
OF value to keep psychrometer,
which Is a simple instrument COM
posed Of two thermometers fastened
to rigid back, the bulb of one ex-
tending below the back and the de-
vice so arranged that 1t can be
whirled rapidly. A piece of muslin
Is put around the bulb which ex-
tends, 1t Is saturated with water and
the psychrometer whired. Both
thermometers are read and the diff
ference noted. The whirling is done
several times. until the reading on
the wet thermometer Is constant
The dew points Is found by +, of a
chart furnished by the Fede~al
weather bureau, the difference in
reading between the wet and dry
thermometer indicating It.
Temperatures Not Fatal
From experiments at Corvallis.
Ore, last spring 1t was seen than an
arbitrary table of temperatures for
frost injury could not be made. In
most OF the tables which are printed
the temperatures between which in
| juries will occur are given as from
~ to 80 degrees. With all kinds of
fruits, both in the Rogue River and
the Willamette valley, it was noticed
that these temperatures did not APP
ply this spring. In many instances
peaches passed through a tempera-
ture of 81 and 2S without injury. In
other cases pears and apples in the
bud were injured at 20 degrees. The
peach is generally considered more
susceptible to frost injury than the
pear, but in one orchard where peach
filters were used with pears, the
pears were about so per cent killed,
while the peaches suffered no injury.
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