The twice-a-week Twin Falls times. (Twin Falls, Idaho) 1916-1918, 1917-04-12

Bridge grating, the use of scions
or small limbs to connect the cam
blum above and below a large wound
or girdled strip, may be practiced sue
cessfully on almost any kind of fruit
tree that can be propagated readily
by grating. 1t is used more often
with the apple than any other fruit,
but pear trees often are treated in
this way, especially in certain Sec
lions. There seems to be no reason
why the method should not also be
successful on plums and cherries.
Peaches, however, graft less readily
and there may be some question as to
the usefulness of the method in the
case of this fruit.
Mechanical injuries which may be
remedied are usually inflicted by ami
mails, by burroWing insects or by inn
plements carelessly used. Various dis
eases, such as pear blight, also cause
local injuries which may call for
bridge grating. The trunks of pear
trees are not infrequently completely
girdled and killed by pear blight.
Bridge grating, if done in time, how
ever, may save the tree. The method
also is useful when large areas of bark
have been killed by sun scald or other
troubles. Protection of trees against
rabbits and mice and disease is, of
course, better than having to bridge
graft to overcome damage.
Grating in Spring.
To be effective, bridge grating
should be done in the spring before
growth starts, though sometimes it can
be done after growth starts if dormant
scions for the purpose can be secured.
Prepare the wound in the tree by
cutting away all dead tissue and thor
Oughly cleansing the injured parts. III
possible, sterilize by washing with a
solution of bichloride of mercury, cop
per Sulphate, or some other antiseptic
The irregular edges Of the bark above
the girdled tract or wound should be
cat back into an even edge, far enough
from the wound to make certain that
healthy cambium is under the bark.
For the grating, select scions from
wood of the previous seasons growth
either branches which grew the pre-
ceding season or water sprouts thai
are only a year old. The scions should
be little longer than the space which
is to be bridged, so they will arcl
slightly over the central part of the
wound.
Bevel the scions at each end of thu
same side of the scion with loni
sloping cut so that the wedge-shape'
ends thus formed will be relativel.
thin and permit their being thrust wei
under the bark without danger of sep
arating 1t unduly from the cambium a
the points of insertion. The placin
of the scions will be facilitated If tn
bark at the margins of the wound
slit for a short distance at the point
where the ends are to be inserted.
Placing Scions.
In placing the scions it is of tn
greatest Importance that the cambiur
of the scions which is exposed In tn
sloping cuts at the ends be brougf
into intimate contact with the can
blum that lies under the bark at til
margins of the wounded area. Th
union of scion and tree can occur onl
where the cambium layers OF the tw
come together. The scions may b
secured in their proper positions,
need be, by driving small ma
through each end into the trunk. Th
will aid in drawing the cambium {
scion and trunk closely together.
The operation is completed by tho
oughly covering the area occupied
the ends OF the SclOnS anu the ma
gins of the wound with grating wa
strips of waxed cloth, or by some OF
er means that adequately will prevel
these parts from drying out. Some o
orators cover the entire wound, sciol
and all, with melted wax. Where Il
bridged portion is below or near II
ground, many operators conserve moi
ture by covering the CRAFTS with cart
Another Method.
Where the wound is so large as
make ordinary bridge grating impo
sible, another method of bridging mi
be used. Two-year-old trees are plar
ed about the base of the injured tire
and their tops grated into Its truI
above the girdled space, which b
first been cleaned as in the other met
cd. AS the tops of the small trees
too large to manipulate readily in t
manner described for scions. V-shap
vertical grooves extending through t
cambium are cut just above the woun
ed area in the bark of the tree to
treated The tops of the small tire
nre shaped to correspond with the
grooves. The two are then accurate
fitted together In such manner as
bring the eambium Of one into conts