The Rathdrum tribune. (Rathdrum, Idaho) 1903-1963, 1913-08-15
APPLE AND PEAR BLIGHT
Disease Found in Orchards Of
This County.
SOME AROUND RArHpRun
inspector Sudweeks Tells How to
Eradicate Disease.

horticultural Inspector Joseph
Sudweeks, submits the following art,.
Gle for publication In the Tribune,
concerning blight in this part Of the
county. Its cause, and treatment
necessary to eradicate this disease.
Mr.. Sudweeks heads his article,
"Pear and Apple Blight:"
Fire blight, affecting pear and
apple trees, is probably the most
serious disease Of fruit trees in the
United States. 1t sometimes com
pletely destroys whole orchards in one
season. The disease Is being found
ia nahy places in Kootenai county
and recently In several orchards In
aud near Rathdrum 1t is seriously
threatening the fruit industry here.
Blight first manitests itself 10 dead
apple and pear lea yes remaining on
the branches. and in the blackened
ana often shrunken condition OF
twi2s and branches. The disease
works just under the bark In the
growing layer of soft wood, killing
the limbs by girdling aud stopping
circulation. Then the rest of the
wood and the bark become darkened.
At first the soft tissue, under the
bark, has u water-soaked appearance.
Blight enters thru the small tw!gs
and travels along the branches down
ward into the trunk Of the tree. It.
Is often seen at the base of a twig 10
the form Of canker-a shrunken
area in the limb with cracks In the
bark. Thru these cracks may be
o0zing sticky liquid varying In color
from whltish to black. The bllghted
fruit shrinks and often gives out
drops OF a similar sticky liquid. This
substance Is of such a nature as to
| attract insects, and it is teeming with
myriads Of the blight germs. The
term "fre blight" is quite appropriate
as the parts affected look very much
as they had been injured by fire.
The disease is caused by bacteria.
true disease germs. 1t winters over
/ Ia the cankers just described and Is
distributed during the spring and
summer by insects which become
contaminated with the disease germs
Of the oozing liquid. 1t is believed
to be distributed principally by bees
in flying from blossom to blossom.
Probably it .1lultiplies 10 the nectaries,
honey sacs, of the flowers. The blight
Is very commonly found beginning at
/ fruit spurs, also IN rapidly growing
shoots, as water sprouts. Wounds
made in pruning or by insect pune
lures or bites. provide entrance for the
germs.
] In district affected by the blight
+, during any season there are always
two general possible sourses of the
disease for the next season. The first
and most dangerous source are the
cankers 10 which the disease holds
over. "If every hold-over cankel
could be removed from an orcharC
district before the sap starts 10 Tho
spring, the disease would be eradicat
ed" The second possibility Is tina,
trees will be infected by insects com
ing from the cankers or honey sacs o
trees already diseased. but IL care Il
taken to remove and destroy al
blighted parts in any district there il
only the possibility OF insects bring
ing the disease from another district
There Is only one method known o
controlling fire blight: that is cuttinl
out and burning all affected limbs a
soon as they are seen. No spray ant
no method Of culture will destroy IL
During the growing season, while tn
disease is spreading, 1t is difficult L
: tell Just how far the affected branche
7 extend. For this reason cuts shOult
. be made some distance below all sign
7 OF coloration or shrinking. Bligh
, may be scattered from tree TO tree II
. this way by cutting into affected part
! with pr ling Instruments. The
there are two good reasons why cut
should be made well down on tn
limbs: to be sure that no disease