East Oregonian : E.O. (Pendleton, OR) 1888-current, 1910-07-05

the work is in the late fall. winter
and early spring. for reasons already
gwen. If an orchard is gone over
carefully by trained inspectors two
or three times and all cases of this
so-called "holdover" blight be cut
| there will be no source of Infection in
the spring and consequently no bios
som blight.
A final and very thorough inspec-
ton Of orchards should be made in
the early spring before the blossoms
open 50 as to detect and remove any
cankers which may have been missed
In the earlier inspections. This is one
of the most important Inspections
that should be given.
The matter of eradication is COM
plicated however, by the fact that
insects may carry the disease con-
siderable distances, and even though
one grower may eliminate hold-over
blight from his own orchard he may
lose large part of his crop by bios
som blight and have his orchard re-
infested by insects carrying the blight
germs from hold-Over cankers in a
less careful neighbor's orchard. APP
pie ana pear trees in town and city
lots are seldom cared for in an up
todate manner and in infected fruit
districts become a very serious men
ace to commercial orchards in the vi
cinity.
How TO Cut Out the Disease.
Where cankers occur on small
limbs or are so extensixe as to nearly
girdle the limbs on which they occur
the whole limb or branch should be
removed. In cutting off such a limb
il is important that one get well be-
low the area of infection. For safety
the cut should be made at least
foot below apparent infection since
in actively growing cankers the dis
coloration of the bark is frequently
so slight as to beeasily overlooked.
Where cankers occur on the larger
limbs and trunks, if not too extensive,
the limb or tree may frequently be
saved by carefully shaving off the dis
eased bark of the cankers to the cap
wood. Here again one should cut well
beyond the point of infection. espe-
NldllN dBONt ana DtiOW lIie CdHhtI
since the germs spread most rapidly
up and down from the point of infec-
ton
In the pear at the beginning of the
dormant period the diseased bark or
hold-over cankers has a characteristic
reddish tinge and with a little expert
ence one can tell how far infection
has occurred In actively growing
cankers in spring and summer it is
frequently very difficult to determine
the extent of the infection vertically
as there may be very little discolora-
tion. In apples it is usually more
difficult to determine the extent of
infection than in pears.
In cutting into the cankers it is
convenient to use a gouge such as is
used by carpenters. This is especially
valuable where cankers occur in
crotches of limbs. 1t has the special
advantage Of making a clean cut that
can be easily sterilized.
Sanitary Measures.
In cutting out the cankers it is ne
cessary that the tools be kept moist
with some good disinfectant. If this
is not done when cutting out an ac-
tive canker each cut will reinoculate
the germs into the bark at the edges
of the canker and the labor may thus
be useless.
Corrosive sublimate in a solution
of one part to one thousand of wa
ter has been found to be the most
satisfactory disinfectant 1t is con-
venient to buy this from the drug
gist in tablet form The solution is a
violent poison and should be so
marked and carefully guarded. 1t
should be kept in glass bottle as it
will corrode metal containers
1t is convenient to carry a sponge or
cloth which is kept moist with the
disinfectant and used to wipe off the
tools after each cut After the pro-
cess of cutting out a canker is COM
pleted sufficient time should be al
lowed for the canker to dry out
thoroughly when the surface should
be carefully disinfected, and then
painted over with white lead paint.
The wound should be kept painted
with a coat of paint till healed over
by the formation of callus.
When cutting out twig blight or
when pruning out badly diseased
limbs the same precaution should be
taken and the pruning tools sterilized
after each cut. All pruned branches
should be Immediately taken from the
orchard and burned. This is espe-
cially important If cutting is done in
summer.
In infested districts sterilization of
all tools after each cut during reg |
ular summer or winter pruning should |
be made a regular practice since it |
might happen that a hold-over cank- |
er be cut into and the tools become !
infected and the disease thus spread |
an orchard.
Methods of Control. !
Spraying with lime-sulphur solu-
tion-winter strength-after the final |
spring inspection and just before the
buds open has been suggested by |
Waite as an aid in preventing the
spread of Fire Blight. An applica-
ton at that time would cover over
any cases of holdover canker and .
serve to disinfect the sticky ooze as
well as render it less attractive to in
sects.