The herald., 1894-09-30
A SERIOUS DISEASE.
Root Rot aud Gum Disease of Citrus
Treos.


Treos.
The following is taken from a recent
address before the farmers institute, at
Santa Barbara, by S. M. Woodbridge.
Ph. d. The subject of this address was
suggested at the last farmers institute
by the Hon. Abbott Kinney, whose trees
at Sierra Madrs Mr.. Woodbridge had
quite successfully treated:
do not propose to ventilate my ig-
norance by giving you learned and
philosophical dissertation on the dis
ease itself. Suffice it to say that the
disease appears to me to have it's origin
in a microscopical insect The differ
ences between the two diseases will
not state. They remind me, however.
of an experience had in Riverside and
Santa Ana. When in Riverside last
spring, l asked why some trees had
dropped go many leaves and oranges.
The answer was that they had had a
"Santa Ana ("Santa Ana'' being a
generic name for an embryo cyclone) /;
and when in Santa Ana last week asked
what was the matter with their walnut
crop, az quite percentage of it seemed
to be blighted or burned, and was told
they had had a Riverside" Just
where the "Santa Ana" begins and the
Riverside" ends it has been impossible
to ascertain. So, where the root rot be-
gins and the gum disease ends l am un-
able to state. The root rot and gum
disease seem to be very nearly allied. l
have never eeen case of root rot where
the gum was not exuding from the tree
above the surface of the ground, al
though have seen many cases whore
gum was exuding when the roots were
not affected.
Gum disease is first noticed in the tree
by semi-hard resinoua gum oozing out
through the bark OF the tree, generally
near the root, and this spreads around
the circumference of the tree and up
into the branches. II the bark 10 cut
away where the gum appears, a yellow
ish rusty-colored slime will be seen
between the bark and the wood. This
same appearance ia manifest beneath
the surface OF the noil in root rot, and
the bark is easily peeled from the tree.
Assuming that animal life was at work.
the trees were treated upon that basis,
and substances were used as washes
that were known to be detrimental to
animal life and harmless to vegetable
life.
Crude commercial carbolie acid was
found to be the best substance, and was
used in varying strengths. When mixed
with its own weight of water it was
found to answer the purpose admirably.
the gum having been previously cut
away 90 that the application could be
do ly n 20 Ha
The result in almost every case was that
the new bark began TO grow over the
diseased parts, at the lines where the
old bark was healthy.
In cases whore the roots had become
affected, the ground was carefully pulled
away from the roots of the tree to the
depth OF from six to ten inches, and,
after day or two exposure, the diluted
carbolic acid was applied, and in the
course of three or four weeks o second
application was made, when the soil
was put back to it's original position,
and subsequent applications of diluted
csrbolic acid we're made, from time to
time, above the surface of the ground.
Coal tar has been found 10 be very
effcscious, also. 1t is applied by tax
ing the soil away from the root of the
tree and putting from one half pint to a
quart, according to the size of the tree,
in the soil about the roots of the tree,
and covering the tar with the soil so re-
moved. Among those 80 treated are
some trees in the famous orange avenue
Of Sunny Slope.
Too much care cannot be exercised in
the uee OF carbolic acid. The strength
of the commercial acid varies. and it
must be diluted to such an extent that
the vegetable tissues will not be de-
stroyed by it,
While on the subject of oarbolic acid,
it may be well to state that dilute so.
luton OF it (say from 10 to rs per cent?
applied to young trees, is an excellent
preventive of the rabbit pest, and
that a little tar applied around the roots
will keep the gophers away. Trees al
fec.ed by either disease should be liber-
ally supplied with complete iertil-
izsr."