The Bennington evening banner. (Bennington, Vt.) 19??-1961, 1917-07-14
POTATO BLIGHT APPEARS
Agricultural Extension Service Of
State University Issues Warning.

Agricultural Extension Service Of
State University Issues Warning.
The weather conditions OF the past
week have been very favorable to the
development of the late blight of the
potato. A careful examination by the
Agricultural Extension Service of the
State University Of potato plants from
plots in Burlington has shown the dis
ease on some of the leaves. The dis
ease appears as irregular dead,
shriyelled, brown spots on the edges
or sides Of the lower leaves, especial
ly those leaves in contact with the
soil. The weather conditions at Bur-
lington (high temperature and hum
idity) have probably been fairly gen.
eral throughout the State. A general
late blight infection is therefore to be
feared. and growers of potatoes,
whether on city lots or in fields are
warned Of the danger to their crop I'M
| less spraying with Bordeau mixture is
carried out soon as possible.
The spray mixture-No better com
pound has been discovered with which
to combat potato diseases than home
made Bordeaux mixture. 1t Is made
of copper sulphate (blue vitrol, water
slaked lime and water. 1t is only a
fungicide and does not kill the Colora-
do potato beetle If combined with
| Paris green or arsenate of lead, both
insect and fungas are attacked. Paris
green is quicker In its action than
arsenate of lead but washes off more
readily and is more costly. Either
works well. Both adhere to the foil
age much longer if applied in connec-
| ton with the Bordeaux mixture. The
spray mixture should be made as fol-
lows: Dissolve 30 pounds copper sui
plate in 80 gallons OF water in a wood
EN- vessel by suspending the crystals
| in a sack over night. Slak 30 pounds
of lime with water and add enough
more to make 80 gallons. These are
the stock solutions. They may be pre-
pared at the beginning of the season
and will keep indefinitely, but must
not be mixed until the day they are TO
be used On the day the spraying is
to be done, put three gallons of the
blue vitrol solution in separate con-
tainer and dilute this TO approximate.
ly 20 gallons. Put three gallons of
the lime solution in another container
and dilute this to 90 gallons. Then
mix the two solutions, stirring rapidly
as they are poured together. The mix
ture should be strained through sack
or piece of cheesecloth to remove the
lime PARTICLES. Stir three quarter
pounds OF Paris green Cor one and one
half pounds dry arsenate of lead) in
a little water until It forms a paste
and add II to each barrel OF the mix
ture. Then add water enough to bring
the whole to so gallons. Time of ap
plication-The first application should
be made when the newly Matched
potato bugs" are seen or the flower
buds appear, usually the first week in
July. The foliage, especially the low
err leaves should be thoroughly cWer
ed. Other applications should be
made at intervals of about two weeks
An application about September 1 Is
especially desirable since late blight
epidemics at this time are usually fol
lowed by destructive potato rots.
Cost Of materials-Two barrels e
the acre should be used, costing
Three pounds of copper sulphate Al
1Sc, SAC; one and one.half pounds Of
Paris green at CSC, S3c; three pounds
of lime at 1c, &c. one application
S1.4O; four applications, $3.50.
The results-Bordeaux arsenica
spraying, II properly conducted, In
sures the crop against blight ant
beetles. No bank should loan money
on potatoes that are not thus cared
for. The protection against early
death from tip.burn and nea.beetle in
jury will repay tn cost of the sprayin,
in years when no blight occurs.