The Oroville weekly gazette. [volume] (Oroville, Wash.) 1905-19??, 1913-08-29
PEAR, OR FIRE, BLIGHT.

So much has been published Of late rel
alive to the pear, or fire, blight that has
made its appearance in this state and
other portions of the northwest, that
anything on the subject coming from an
authoritative source is read with inter-
est by orchardists. The following article
on the subject is issued from the U. s.
Department of Agriculture, and recon-
mendation and information from that
source should carry great weight 1t Is
government answer to critics of its
methods of combating pear blight, and is
issued under a Washington. d. c., date:
The Department of Agriculture has re-
ceived notice by telegraph from citizens
in the state of Washington that certain
people are spreading the idea that the
pear blight is not a bacterial disease,
and that the departments recommended
ton that pear blight can be dealt with by
cutting out the diseased portions of trees
is not an effective measure.
In the fear that these unscientific Opin-
ions may stop orchardists from following
the highly successful practical measures
recommended by the federal specialists,
and thus lose their own orchards and
spread the disease among neighboring
orchards, the department has issued the
following special statement:
THAT pear blight is bacterial disease
of the pear tree is not open to question.
The scientists have clearly established
the existence of these bacteria by means
of microscopic examination, and have
reproduced the disease by inoculating
fruit and trees with them. The germ Is
the bacillus amyovorus. 1t is an oval
shaped body and is 1.1800O of an inch
long and 1.25000 of an inch across, and
can be clearly seen with a high power
microscope. Moreover, the scientists
have raised these bacteria in their lab
oratories and have used them a large
number of times in experiments to in
feet healthy trees and fruit. Wherever
this baculus has been introduced into a
healthy tree or fruit the pear blight has
followed. The scientists also have proved
that the pear blight can be commune
Gated from the blossoms of an affected
tree to healthy trees by bees and other
insects, and that the blight that is held
over through the winter can be commune
Gated to healthy portions of the same tree
or to other trees by flies or other insects
Pear blight differs radically from the
peach yellows in the way it affects a
tree. The peach yelows does not show
i'Stll tulWdiuly Ill II tree until the entire
tree is affected and cannot be saved The
pear blight on the other hand, has a
purely local effect and attacks certain
blossoms, twigs, branches, or a section
of the bark. and leaves the rest of the
tree uninjured except where girdling has
occurred.
In thousands of orchards, and in the
case of hundreds of thousands of pear
trees, especially in California, and Ore
Son, particularly in the Medford district
1t has been proven that by cutting out
the portion of the tree affected by the
pear blight and washing the cut with a
solution of one part of corrosive SUBJ
Innate Ga highly poisonous substance) to
1000 parts of water, orchardists can save
most of the individual trees and prevent
the spread of the disease throughout their
orchards. II therefore strongly urges or
chardists in districts affected by pear
blight to continue to cut out affected por-
tons of the trees and wash the cuts with
this mixture. In cutting they should
wash their tools in this disinfectant, SO
that the tool itself cannot communicate
the bacteria to healthy parts of the trees
Especially orchardists are strongly ad-
Vised to so over their orchards very care
fully in the fan and cut out all cases OF
hold over blight. in order to prevent the