Daily Kennebec journal. [microfilm reel] (Augusta, Me.) 1870-1975, 1918-08-01

was ISSUED today from the once OF
charles D. Woods, director Of the
Maine agricultural experiment sta
ton:
Il was rot until the fall Of 1906
that the Maine Agricultural Expert
ment Station had the services OF
trained plant pathologist In the
wears that had preceded that the
work on plant diseases was various-y
handled. The first published re1er-
ence to the use of Bordeaux mixture
by this Station was in short bulie-
tin by the botanist and entomologlst
in 1889. 1t was not until 1896 that
tests Of BORDEAUX mixture as con-
troll Of the late blight OF potatoes
were made at this Station. And not
until 1900 that the large series OF
exnerimepts. which resulted IN
Aroostook county adopting spraying
with Bordeaux mixture as funda-
mental in potato culture, were car-
ried out.
Bordeaux mixture was an accident
al discovery in connection with con-
troll Of grape diseases. It's appilca-
ton to potato blight was logical.
But the preparation of the material
was. and still is. more or less arpl-
trary. Six pounds of copper sulphate
and pounds of quick lime about
balance each other chemically. AND
this was the proportion, win oo gar
Ions of water. that was for long
time used. But if the lime carried
mich sand. it would not neutralize
the copper sulphate and the tops
would be injured. Also paris green,
which was used as the lnsectlclde,
carried free arsenious acld ana mat
also burned the tops. Hence lorfh-
ula carrying less copper ana more
lime came into general use. the
snraying outfits first used IN Name
an notatoes consisted of an oil bar
rel with pump. An oil barfei holds
about so gallons. For ease OF mem
orv and convenience of measure, TINS
Station recommended the 5-o-30
formula which is now used by potato
growers in this State. Experiments
with much weaker solutions have
not, in bad blight years, given SUI
nclent tbIllIpl " " al am iN~OAAA
mending their general use. stronger
mixtures have not given better re-
suits. So this formula, somewhat
accidentally proposed seems to MT
the case.
The value of Bordeaux mixture de-
ponds upon the copper it contains
the chemical form it is in, and its
made Bordeaux mixture has the cop
per present as hydroxide, will stay
in suspension and only settle out
slowly. A commercial Bordeaux mix
ture to be satisfactory must have the
above properties. No commercial
! article as now placed upon the MAJ
ket and used in accordance with the
F.! directions will carry as much copper
| as a $3.50 formula. Freshly made
| properly prepared Bordeaux mixture
| is in a gelatinous form. This re-
mains in suspension and adheres
well to foliage. Gradually it under
goes chemical and physical changes
1t becomes crystalline and settles gu,
! faster and does not cling to foliage
as we'll None of the commercial
| Bordeaux mixtures that this Station
has tried stay in suspension as well
as freshly prepared Bordeaux mix
ture. and some of them settle out al
! most Immediately.
The Bordeaux preparations regis
tered for sale in Maine carry as re-
qured by law. the statement of the
| iva Ioyr
This varies from 2 to II per cent
To make a mixture equal in copper
content to a $3.50 Bordeaux mix
ture it takes 63.6 pounds of a COM
mercial mixture carrying per cent
copper, 2S2 pounds of a Az per cent
II pounds of a IN per cent. al
pounds Of 9 per cent and 1o.6
pounds of a II per cent commercial
! article.
The ingredients to make so gallons
of home made $3.50 cost at present
| prices from 55 to Is cents. From the
claimed per cent of copper on the
label of the commercial Bordeaux
| mixture t is planned to use and from
the preceding paragraph the number
of pounds that will be needed 10
make a barrel of proper strength is
readily found. Multiply the cost pei
pound by that figure and its cost is
had. If 1t contains an insecticide i,-
value must also be taken into con-
sideratioa. At present prices the IN
secticide used with so gallons OF
water will cost from % to 60 cents
| Hence, barrel $50 gallons) of home
made Bordeaux mixture with the
insecticila will cost from 80 cents &c
$135 for the ingredients. In most OF
the commercial Bordeaux mixtures
there is relatively a high amount OF
insecticide. Hence. if they are used
in sufficient quantity to supply the
needed copper to make the equivalent
of a $3.50 mixture an unnecessary
amount of insecticide is used.
One of the best of the commercial,
Bordeaux mixtures and insecticides
registered in Maine carries IL pei
cent copper. The samples purchase
by the inspector cost at the rate OF
IS cents a pound. 1t would take
1O.6 pounds of this mixture to make
so gallons of a mixture carrying as
much copper as a $500 Bordeaux al
a cost of sg65 for the materials. An
other registered preparation carried
per cent copper This was SOLD e
the inspector at the rate OF IS cents
per nound. 1t would take 63.6 pounds
of this to make SO gallons carrying
nc much as $3.50 and would cost