The Rock Island Argus and daily union. (Rock Island, Ill.) 1920-1923, 1920-07-26

Medicine for Trees.

ditions and the World wag and i,
is understood that it has not ~
resumed.
In Germany, before the =.
medicine for grape vines and f,,.;.
trees was subject of exten.iss
study. The German farmer A..
.long been taught to know the ,, ~
OF every piece of timber a. ~
land, SO that he welcomed the =, ~
method ot.attacking disease *.
German experiments, like tn ~. =
sian, were interrupted BY tia -.
SO that just now the only count,.
that Is known to be working esrs
cially on tree injections is Enrl,rs
United States agricultnr,,,.
were several years ago greatly i.
terested in the possibilities Of -. &
injections, because they were mn.
posed as remedy for the terrihl.
chestnut blight, which has destroy.
ed millions OF our valuable trees
Injections for Trees.
DR.. Caroline Rumbold, a patholo.
gist connected with the departmer, !,
OF agriculture. is the only scientist
in this country who has studied ths
effect OF different chemicals when
injected into the tree system. Tss
work, she says, was battling and
very slow. In the first place. she
had trouble in getting any kind AZ
liquid introduced into her tree ma
tients.
Sap" she explains, does not
circulate like blood. Instead. the
wood contains numerous tube-like
cells, through which the crude san
Is conducted to the leaves to be
manufactured into food. The food
then returns to the roots and other
living parts through the inner
bark again, but it does not spread
through the tissues of the tree as
1t would if the trunk were thread
ed with network of veins like the
human body. In order to inject a
tree evenly on all sides, it is neces-
sary to make a number of injec-
tions on different sides of the trunk.
and even on the limbs. This means
that many quarts of a very dilute
chemical solution must be put into
a tree if the chemical is to reach
all portions of it. If only a small
amount Of concentrated solution
were used, it would kill the cells
near the injection hole and would
not reach other parts. This is one
of the reasons why boring a hole
in the trunk and filling it with
strong chemical, in either solid or
liquid form, is not likely to benefit"
Some of the Sc solutions which
! DR.. Rumbold tried on the chestnut
! trees were fatal. But she did find
one, lithium solution, which
stopped the growth of the chestnut
canker. Some Of the lithium, she
found, was carried into the nuts II
the trees were treated in the fall.
Rats fed on these nuts, and also on
nuts from trees treated with other
solutions, showed no signs Of i'll
ness, however, so that it was be-
lieved that the amount of chemical
which would occur in the fruit Of
injected trees would be negligible.
An Impractical Method.
After four years of experiment,
DIR. Rumbold reported that inject
ing trees was not a practical means
of putting an end to the chestnut
blight because of the expense. The
lithium solution, she explained,
was not exorbitant. but the rate,
which competent tree doctors
|, would have to charge for their
services would make it scarcely
worth while to have a blighted or
chard treated. Another drawback
was that the effects of the lithium
solution lasted only year. BY that
time the chemical had worked en-
tirely out of the tissues Of the tree
so that 1t was no longer immune 70
the disease. This condition is SINH
lar to that experienced by persons
who are vaccinated against small
pox. or inoculated against typhoid.
The protection lasts only for a Ger
tain period of time.
As the short immunity and the
expense made tree medicine In
practicable in treating the wide
spread chestnut blight. DR.. Rum
bold's experiments along that llns
stopped. She says, however, tnat
the study OF tree injections is only
begun, that the method has posi-
bilities, and that while 1t IS no.
| suitable for wholesale decorating Oh
large orchards under present con-
ditions, it still may prove valuapis
| in the treatment of other diseases'