The Colorado statesman., 1908-09-12
DANGER EXISTS IN THE TOO CON.
TINuoUS USE OF ARsENIcAL
POISON
AFFECTS TRUNK ROOT
RESULT OF INVESTIGATIONS BY
THE COLORADO ExPERl-
MENT STATION.
(By DR.. w. P. Headden.)

(By DR.. w. P. Headden.)
"Arsenical Poisoning of Fruit
Trees" is the subject of a bulletin
prepared by DR.. William P. Head
den. professor of chemistry and geo
logy at the State Agricultural Col
lege, and issued by the agricultural
experiment station. This bulletin
is the result of an investigation con-
Quoted by DR.. Headden to determine
the cause of the death of so many
fruit trees ON the western slope and
in the Arkansas valley, which inves-
tigation, followed by scientific tests
has led him to the conclusion that
the trees are suffering from ,systemat-
ic arsenical poisoning, lime poisoning
or both, due to the use of arsenic in
spraying tbs trees. DR. Headden
has gone into the subject exhaustively
and is unable to reach any other con-
clusion.
Speaking of means for preventing
the death of fruit trees from this
cause. DR.. Headden says:
Il have no remedy to suggest for
either condition. Preventive meas.
ures are so far as / can see, our only
recourse. Those which suggest them.
selves to me are: to remove the ar
Senic laden soil from about the crown
of the tree and replace it with fresh
soil; to nse the standard brands Of
lead arsenic in preference to the arSen-
ite of lime or white arsenic sal soda
and lime; to use as little lead arsenic
as possible. | have been told that good
results have been obtained by using
two and a half and even two pounds
of pasty lead arsenate to 100 gallons of
water, but the spraying must be done
thoroughly.
SPRAY no oftener than is absolutely
necessary. If l am not mistaken Prof.
Gillette has found that ninety-five per
cent. Of the effect of the whole sea
sons spraying was obtained by the
first spraying when thoroughly well
done. Some device should be u3ed to
prevent the spray material from run
ming down the trunk and collecting at
its base or it would be still better to
make provision for gathering the whole
of the drip. Water rich in alkalies
should not be allowed to flow close
enough to the tree to permit of the
disposition of the alkalies in the soil
about the trunk of the tree. Concen-
trated lye, If used to kill the kooly
aphis should not be applied to the soil
at the crown of the tree or permitted
to flow down and collect there"
In summarizing the results of his in
vestigatiols and tests, he concludes the
bulletin Nth the following:
First-There is a large number Of
fruit trees in the state which are
suffering from an affection of the trunk
root
Second-This trouble begins in by
far the greater number of cases. at
the crown of the tree and subse-
quently involves both trunk and roots.
Third-The first marked symptom IS
an early ripenirg of the foliage usually
followed 10y death about midsummer
of the ensuing year.
Fourth-The crown of the tree is
found to be girdled, the bark on por-
tions of the trunk dead and sunken and
most of the roots dead their bark de-
stroyed and the woody tissue discoI.
ored, usually a light shade of brown
and sometimes exteriorly blackened.
F1fth-Soluble arsenical compounds
will effect the destruction of The bark.
the staining of the wood, the produc-
ton of the socalled "black heart" and
the speedy death of the tree.
SiXth-Arsenical sprays have been
used in these orchards for a number of
years.
Seventh-These arsenical compounds
have accumulated in the soil.
ElSntn-lne accumulation in the soil
in an insoluble form has already passed
far beyond the limit of danger for ar.
senics in a soluble form.
Ninth-The insoluble arsenical com.
pounds are being converted into solu.
Bile ones in the soil.
Tenth-The alkalies are the agents
effecting the solution of the arsenic. By
alkalles, | mean, sodic carbonate So
die sulfate and sodic chloride.
Eleventh-The lime salts. viz. tba
sulfate gypsum and the carbonate do
not effectively protect the arsenical
compounds from the solvent action of
the alkalies.
Notwithstanding poisoning NAV
take place, probably does by absorb.
ton OF the arsenic with the nutritiva
solutions taken up by the feeding roots
but the greater portion of the trouble
appears to be from local irritant pois.
oning.
Thirteenth-Thea arsenical poisoning
Is, In all probability, in many cases
complicated by lime poisoning.
Fourteenth-The arsenic in tba ,r.
senate or lime is more readily broupbt
into solution than that of the lead ar.
senate. ''u "i
F1fteenth-It Is probable that the
lime or mari in the soil and subso;1 10
also an agent acting conjointIv With
the arsenic in producing some of tba
trouble. 'i'
me wheat crop this year was cut