The Mitchell capital. (Mitchell, Dakota [S.D.]) 1879-1918, 1906-06-15
PorA1o scAR.

because In some years potato scab in
more troublesome han in others, and
because the disease Itself is so little
understood by practical growers, there
is danger of its not being regarded
as OF the Importance that it deserves.
n common idea that potato scab IL
produced by chip dirt, ashes OF some
thing of that kind is erroneous. 1t 10
a funsous disease, and grows from
spores, the same as any other fungus.
Certain condilions favor its growth,
and such favorable conditions may b9
furnished by chip dirt, lime, ashes.
etc. When once introduced into land
no practical way has thus far been
ound of removing il. How long it will
email in the soil is unknown. 1t GER
tainly may continue for many years
ever when no potatoes are grown upon I
the field.
There are many ways In which it is
possible for soils to become affected
The germs may be introduced into his
manure pile by feeding scabby p%otatces
to live stock, or by putting them direct
ly into the ccrmpos heap. The fungus
may then propagate itself in he ma
nure, and if this is applied to the land,
the disease may be Widely Disseminated.
Alkaline soil favors the growth OF the
fungus. and on this account neither
ashes nor lime should ordinarily be
used in connection With potato grow
ing. As farm anur are Slightly
dAiAGsllHC, lICS GlG DSSI lioS ooFN1 III M
tato land. The blowing under of a
green crop tends by its fermentation to-
make the soil Slightly acid. This con-
dition is unfavorable to the growth OF
he fungus. There is q more OF les
common belief that salt is something
Of a preventative of potato scab, but.
exact experiments have failed to DEM
onstrate this.
Perhaps the most common way in
which the scab fungus is disseminated
&c 1Hy f1N ,,~1 -F~a%- -le7 TAAs-
therefore of the utmost importance to
use clean seed. Where it is impractac-
able to procure clean seed, or in case
of doubt. it should be treated with a
fungicide. While such treatment WIFI
help scabby seed. it may not act as
an entire preventive. Il is therefore
best not to use seed that is much at
fected.
Formaldehyde gas, either in solution
or in the dry, gaseous state, car be
seed. Fornaldehyde (forrnalin) is sold
in a solution of about 40 per cent.
strength, and can be obtained at any
drug store. a few bushels of seed are
most conveniently treated as follows
Make up q solution of fornlalin of the
analin Gao per cent. solution of formal
dehyde gas) to each so gallons of wa.
ter. Soak the seed two hours in thiss
solution, and then spread out the tu-
pelS W uiy. AIlef QTylilS Ine potatoes
should be cut n planted in the usual.
way, but care should be taken not to
allow them to touch any boS, bag or
bin Where scabby potatoes have been
kept.
The Vermont experiment station is
studying the treatment of formaiae-
hyde gas, and while they have no.
reached perfectly definite conclusions,
they recommend the following treat
ment for potatoes in bins: .
The bin or room where the potatoes.
are stored should be closed as tightly
as possible. Ten ounces of forlnalin
should be used for every 1000 cubj:
feet of room, n the potatoes should
be left exposed to this gas for twenty
four hours. The gas is generated by
the action of formalin upon potassium
parts by weight of potassium pern1an-
Eanate are mixed with eight parts of
formalfn in an earthen jar. The lar
should have a capacity of about a gal-r
lon for each pint (16 ounces) of fpr-
malin. The required amount of per-
manganate should be placed in the bot.
tom OF the jar, and the needed amount
orator hould leave the room at once.
taking care to close the door as tight
ly as possible. h retail cost of TIN,
chemicals to produce gas for l,OO0 GU
bic feet will be about $1.5O.
For handlers OF seed who wish to in
sure freedom from scab and for large.
rover of potatoes this gaseous meth
% IS more convenient than the wet
method, and experiments at the. Yer
mont station show it to be effective
Charles d. Woods, Maine Experiments
Station.
Sets Limit to His Patience.