The Savannah morning news., 1900-06-18

Pear Blight.
We are receiving quite a number of in
quiries concerning pear blight and best
known remedies, writes Prof. Price of the
Missouri Experiment Station. We desire
10 call attention to some work that has
been done along this line especially by
the United States Department of Agri-
culture, and which should be known by
many of those who are growing pear
trees; but it appears there are many who
are not familiar with these results. Pear
blight has been discussed in Farm and
Ranch at different times very thorough
ly and we will not enter into a discus
sion concerning its life's history and the
appearance of the germs that produce it,
at this time. The fact is we'll establish
ed that pear blight is due TO bacterial or
ganisms. These organisms have been
examined by our classes in the study of
mycology at different times. Our students
have also inoculated healthy trees with
the germs of the disease. This usually
can be done by using some of the fresh
~ diseased wood, or, better, some of the
exudatons the stems of the leaves
and of the twigs, by inserting some small
parts of these just under the bark of an
actively growing shoot. The NEGOTIATIONS
may be Difficult TO take" sometimes when
made late in the season, after the sap is
not so active.
So far as I know, there are only three
lines of eatment TO follow in regard TO
this most serious disease of the pear, es-
pecially in the Southern states. First,
cut out the disease parts some twelve to
eighteen inches below the diseased It's
sues and burn them. This should be done
very carefully late in the fall, after the
leaves have fallen off the trees If this
i- An1a fhara Ia - x.Ea
ton of the pear trees the following
spring, except from nearby orchards
where the cuttings have not been closely
cut out and burned. These cuttings should
be made by the concerted action of all
growers in an immediate neighborhood,
and thus make an extensive effort to
stamp out the source of infection at this
time of the year. This is the most prom
Using line of treatment so far known to
scientific investigators that 1 am aware
of.
There are one or two parties in the
states who are selling preparations known
as Pear Blight Cure" One of the prep
arations has been tested by US here and
proven TO be made largely of corrosive
sublimate. This material was recon-
mended to be put into the tissues of the
tree, just under the bark, and the sap
was said to carry the poison to all parts
of the tree and kill the germs of the
disease. MS MATERIAL Wnen put INTO a
tree in small quantities late in the sea-
son. when the sap is not so active and
the disease is also very inactive at this
time of the year, not much damage was
done 10 the tree by a small quantity of
proison. and the conclusion has been
reached by some that this treatment kill
ed the pear blight disease. The conclu-
sion, in some instances, was entirely err
roneous After experimenting along this
line, we find that corrosive sublimate will
injure the pear tree when used in any
considerable quantity, and inserted under
the bark when the sap is active. I,
therefore, warn all parties not to depend
upon this treatment.
The next line Of treatment is to plant
the most resistent varieties Just which
are the most resistent has not been clear
ly demonstrated, but the Kieffer variety
Early Harvest and Smiths Hybrid seem
to resist the disease fairly we'll
The next line of treatment is, not to
cultivate the ground 100 much after trees
are nearly grown and ready to fruit so
as not 10 force so many young, tender and
vigorous growing shoots into active grow
ing. They are most likely to be attack
ed by this germ disease. The disease
most frequently makes ifs appearance
during the time when trees are bloom
ing. The germs are carried 10 the
blooms by insects and wind, and when
they once get a hold in an orchard by
this means the disease is hard to eradI-
| cate.
We frequently have inquiries as to
whether she disease should be cut out OF
the trees in the spring This Is a very
costly process in large orchards, and
hence il is a question whether 1t should
be cut out then or not. If the disease
appears in only "A few places I would
by all means, cut out and burn the dis
eased portions We have records of pear
| orchards thet have been constantly spray
ed during the growing season AMI but
| little blight appeared. but whether this
| continued spraying, which IS yer, cost
| " on large trees. would continuously
| keep the orchard from being affected.
where nearby orchards are affected, has
not been clearly proven.