The daily sentinel., 1902-10-30
TO FIGHT BITTER Rot
UNIVERSITY OF ILLINOIS SENDS
OUT GOOD ADVICE.
This Disease, So Disastrous to the Ap-
Pile Growers, Can Be Prevented II
Proper Precautions Are Taken in
Time-An Important Work.

Bitter rot, the disease which has
sometimes proven so disastrous to the
apple grower, has already been found
this year widely distributed through
out the chief apple growing regions of
Illinois, and it has probably made the
same start elsewhere. 1t is never
greatly developed at this season of
the year. but sharp observers are able
to find it when there are but lew in
fected spots on the young apples.
1t is matter OF common knowledge
that the fruit first infected in tree
| occupies definite position in the
| branches. In general terms, it may be
| said that the disease shows in a conf
cal shaped area with the apex upward,
| and this has been explained by the
fact that the spores of the fungus are
adhesive so that they cannot be dis
tributed by wind but can readily be
washed down by rain. The primary
infection at the apex OF this cone, COM
monty supposed to be an earlier dis
eased apple, furnished it was thought
the spores which started the disease
L in the fruits underneath. 1t has now,
however been ascertained that this
primary infection starts in a canker
upon the limb of the tree. In this sit
uation tho fungus lives over winter
and as early as sometime in June be-
gins to produce spores by which the
young apples are infected. 1t is not
usually easy to discover the cankered
spot from the ground, but it is easy to
locate it Ly the diseased spots on the
apples. With little practice any one
with eyes sharp enough to detect these
latter can quickly find the former. 1t
seems, therefore, entirely feasible to
prevent further infection by critical
examination of the trees at this time
i Of the year and the removal Of the
cankered limbs and the fruits already
diseased from it.
Il Canker occurs on limbs Oh any size
from those of an inch or two in di-
ameter to last years fruit spurs.
More commonly the spot is two to
four inches long.
Il From what Is now known, the fol-
lowing preventive procedure is ad-
!: vised: Examine the orchard tree by
tree, following systematically the rows
perhaps on horseback or in some
way to look down as much as possible
upon the fruit, the infected spots be-
ing usually on the upper surfaces OF
the apples. At this time of the year
these spots are brown, circular and
very slightly depressed and show
clearly against the light or reddish
color of the apple. AS soon as one
spot is found search for others and
just above the uppermost ones look for
the cankered limb. This limb is sure
to be in such position that spores
may be washed from it onto the spot
ted fruit 1t will now be an easy
matter to cut away the diseased limb
and to remove the infected fruit below
it. 1t will be safer, however, to take
all the apples from that portion of the
tree subjected to infection from the
canker for it may not be easy to find
the very small spots where the fungus
recently started. Cut well below the
cankered spot, avoiding the rubbing of
the infected area by tools or hands.
The operator who goes into the tree
top for the purpose of making exam
nations and removing cankered limbs
should be provided with rubber boots
or thin-soled shoes, so as to not in
any way cause the rupture OF the bark
when climbing about. All diseased
limbs and fruit from the trees should
at once be put into wagon or other
receptacle and removed from the or
chard, where they will be either burn
ed or buried deeply in the ground.
Experiments carried on this year by
the University of Illinois prove con
clusively that bitter rot can be very
largely held in cheek by Bordeaux mix
wb have
more cankered limbs. 1t is believed,
however, that a critical examination
of the trees and the removal of the
source of infection as described is the
most important work the orchardisi