The herald., 1896-10-17

by the organism. Under natural condi-
tions the nut of the Persian tree is very
commonly infected in the blossom. at
or about the time of pollination. Second
ary infections may take place through
any portion of the hull of the tender nut,
especially during the more rapid growth
of spring.
The new shoots and leaves may be in
fected at any portion which Is tender
ard rapidly growing, but most of these
infections actually take place at or near
the growing points of such shoots, and
only become distinct to the naked eye
after rapid growth has left the infected
part some distance down the branch.
Injury to the cells of the nut, branch or
leaf parts is effected by the organism
by means of an enZym. or ferment This
enZym acts chemically upon the tissues
surrounding the point of infection, de-
stroying the cells and preparing them
as pabuium for the multiplying bacilii.
The enZym is capable of destroying the
tender cells of the hulls, newly forming
shell, and the contents of the kernel.
AS any or all of these parts become hard
with age, less injury is done through in
fection by this germ. In case of blossom
infection the nut is badly diseased. and,
in majority of cases, will fall when
one-third or two-thrds grown. Later
! al infections of the hull are less likely to
! wholly destroy the nut but very COM
monty cause it to fall, or the hull to ad-
hore to the she'll in such a manner as to
! make the nut unfit for market Wher-
ever the nut becomes infected the parts
! eventually turn black, owing to the OK
idation of the tannic acid When the
disease is actually spreading. however,
circle next to the healthy tissue usu
ally assumes a watery appearance.
which may be used az characteristic
| quite distinctive of this disease This
watery ring is where the enzym is acting
upon the healthy cells, often in advance
of the presence of the organism itself.
The characteristics here given for in
fected nuts are equally applicable to in
fected branches.
The germs of this disease are capable
of wintering either in the diseased
branch or nut
The treatment of walnut bacteriosis
mas already shown some beneficial re-
suits. over forty acres of spraying ex-
perlments were set on foot last spring.
This work was done with the leading
fungic1des. but as the disease is now
known to be of bacterial nature it will
be attempted to prevent the same by
| means of some of the leading germicides.
with which. applied as winter sprays it
| is hoped to obtain even better and
| cheaper results than with the standard
| fungicides. AS this work is still in pro-
| gress. and certainly cannot be complet-
GU iiSiue VI SHotiIer year, IL cannot De
summarized al this time. 1t may be
said. however, in absence of the perfec-
tion of better methods, that the Bor-
deauX mixture applied to the tree just
| before the growth of spring starts. and
again to the nuts as soon after polina-
tion as possible. will certainly prevent a
portion of the infections which would
otherwise take place.. 1t has also been
found of advantage to gather and de-
stroy diseased nuts, and to prune away
diseased branches during the winter. 1t
is hoped that another season given to the
testing of germicides may develop some
more specific manner of preventing in
fection or treatment looking to the cure
of diseased nuts or branches may be
hoped for; all treatment must be pre-
ventive. NEWTON B. PIERCE,
Assistant United States Pathologst.
Santa Ana Sept 16, 1896.