Vermont phÅ“nix. [volume] (Brattleboro, Vt.) 1834-1955, 1894-07-13
POTATO BLIGHT.
Inc Use of Bordeaux NIixturo
recommended.

'O'iohs Tor Making an,I A,,.,t.
ing "iNeh by Prof. Jones of the r.
pertinent Station.
we are satisfied after five vaars, o,.,,o.,
Irce mat 1t pays to spray ali nototoas -,
OCernlonJ with this Bordeaux mivtnra
our potato vines are attacked NV ty,o AZ
oiiy I, OHghts. The early blight attaci,s
eaiiIer potatoes, spreading SLOWLY in Tnlv
anu august, causing premature death of
vines, put no rot. The late blight attacl,s
laUer potatoes in August and Sentonnhor
spreading rapidly in warm, moist weather
anu Is followed by rot. The early bligbt
Is a complex trouble caused bv the attaSils
Vi insects as well as fungi. IL is ALREADY
appearing on early potatoes. BEING n com
pllGaled disease, it is less perfectly con
I[olled by spraying than is the late 6licbt
Cur results last summer showed that IT. can
De at least partially checked by Bordeauv
mixture The late blight and rot is q fnng-
GUS disease, and Bordeaux mixture nronoT-
~ applied is an almost perfect remedy Nv
us use we have invariably kept our later
potatoes alive through September and have
loSI nut very few from rot. The re-
suit mas been that our yield of later nota-
toes mas been more than doubled by sprav-
ing Every potato grower should trv if
Ihls SUMMER especially on medium and
late potatoes.
-. Inc formula for. Bordeaux mixture is.
rive pounds copper sulphate five pounds
lime Unjust be fresh, not air slackedD 80 cal
Ions Tone bareD water. Dissolve the COP
per sulphate in clean wooden or brass
vessel, slack the lime i'm another vessel
then dilute with water to a thin white
wash and strain it into the copper solution
sur thoroughly and add water to make
about % gallons tone barreD.
The following suggestions may prove of
USE
l. Keep yOjT mjrture cieaH. Chips lumps
of lime, etc, in theImiXulre will clog pumps
or nozzles. Therefore, thoroughly clean
all vessels to begin with; strain all water
and copper solutions through cheese cloth.
unless they are perfectly clean. Strain the
lime whitewash through some coarser cloth
or sieve and throw away all the dregs and
humps.
=. To diSSolre dlue rjtriol 1t NAV be
quickly dissolved in water by heating in a
brass kettle to the boiling point, or by
pouring boiling water over it. The most
convenient way we have found, however, is
to dissolve in cold water by putting it in
coarse sack and suspending this in the top
of tub or barrel of water. As fast as
the heavy solution forms it settles to the
bottom and fresh water rises. BY using a
gallon of water for each pound of blue vtriol
it will dissolve in a few hours in this way.
3. Keep Il stock SOiutjoH We find it
most convenient to dissolve considerable
blue vitrol at a time in the above manner,
and to keep it on hand in a covered barrel.
We put in a pound of vitriol for each gal
lon of water, and as we wish it from time
to time we simply stir it up and dip out as
many gallons of the solution as we wish
to use pounds of blue vtriol.
1. Othcr c0HUeaicM methods. To avoid
the trouble of weighing the blue vitriol
may be measured out five pounds equals
two quarts) and the lime added by test.
This test consists in pouring few drops of
solution of ferro-cyanide of potassium Tone
ounce in four ounces of water) into the
mixture. If there is not enough lime in
the mixture this solution will at once turn
brick-red, but if enough lime has been
added there will be no change of color.
5. Caution. Strong copper sulphate
solution alone will kill the leaves. Freshly
Stacked lime neutralizes the sulphate and
prevents this caustic action. If not sure
that the lime is fresh or good or that
enough is added, the mixture should be
tested as described in No 4, or few plants
only should be sprayed at first to test its
action.
6. Potato bcetleS Bordeaux mixture
alone will not kill the potato bugs Add
Paris green when needed at the rate of one
half pound to 30 gallons.
:. when 10 spray. Remember that
Bordeaux mixture is a preventive, not a
cure, and the first application should be
made before the disease appears. The fol
lowing dates for spraying potatoes are based
on our experience at Burlington.
Early potatoes planted April to May >
spray about July l, -, August l, and
again if needed.
Medium potatoes planted May to May
Il spray about July -, August l, 10 and
again if needed
Late potatoes planted May 10 or later
spray about Aug l, Aug. IA, Aug. Is, and
again if needed.
s. Holv to dppiy. The mixture may be
put on in any way so as to cover the upper
surface of all the leaves. The best way
to do this is with a force pump which has
good spraying nozzles attached. Untortu-
nately, but few have these pumps. APP
plying with a common watering-pot or
with pail and a broom or wisp OF hay
takes more time and patience, as well as
more of the mixture, but if thoroughly
done will give good results. In most cases
where watering-pot is used it will work
better if the holes in the rose are enlarged
with an awl. Apply thoroughly; it will
not injure the vines, providing the mixture
has been properly made.
Further information will be freely given
in answer to any letters of inquiry.
L. r.. JONES, BOtdHiSt,