.S September 21, 1912
UNIVERSITY OF FLOMIA
AGRICULTURAL EXPEMMENT STATION
PROTECTING CORN FROM WEEVILS
By C. K. McQuarrie
The destruction of grain by weevils causes an annual loss to the corn-
growers of Florida of from 15 to 25 per cent. of the total crop. The value
of last year's corn crop was estimated at about $8,000,000, and the loss to
the farmers from weevils must have been more than $1,500,000.
Better Cribs Needed
This large loss can be checked by building a better kind of crib than that
in ordinary use on the Florida farms, and by fumigating the stored ears with
carbon bisulphide. In harvesting the corn, we should also shuck it clean,
so that there will be nothing on the ears for the weevils to hide under. To
get good results from fumigation we must have tight cribs or granaries. The
ordinary crib is too open. Any of the existing cribs can be made tight, pro-
viding that the framework is substantial, by lining with matched lumber, and
making tight-fitting doors and windows. A crib that will hold 400 bushels of
clean-shucked corn in the ear will measure about 12 by 12 by 6 feet. Eight
hundred and sixty feet of matched lumber will line and cell it completely.
With ordinary lumber, nails, and labor, the cost need not exceed $20. Second-
grade lumber, if free from knot-holes, will answer the purpose. The cost of
thus fixing up any of the ordinary cribs will be more than returned in one
season in the value of the corn saved from the weevils.
Hiow To Fumigate
Level off the corn in the crib, and lay saucers or deep plates about 4
feet apart over the surface of the corn. Into the saucers pour enough of the
carbon bisulphide. A gallon of the liquid will fumigate from 500 to 600 bushels
of corn. Then close tightly all the windows, doors, and ventilators. Cracks
round these can be battened up with sacking. Leave closed for 48 hours.
The fumes of carbon bisulphide are heavier than air and will penetrate into
PREFSS B ULLBTIN I i$,
every crevice and kill the weevils. But many of the eggs of the weevils will
not be killed. After two weeks repeat the fumigation, so as to kill all the
weevils that have hatched from the eggs.
When small quantities of corn are to be fumigated, fill large air-tight bar-
rels with the corn, lay a saucer or soup-plate on the top, pour in two table-
spoonfuls of the liquid, and cover up for two days. A good method of making
an air-tight covering is to put a heavy coat of axle-grease or vaseline on
the rim, and then apply a sheet of thick paper with sacking to keep it in
The expense of fumigation is small compared with the resulting gain.
Carbon bisulphide can be Ibought retail for about 35 cents a pound. In
handling it, much care should be exercised to keep it away from fire. No
smoking should be allowed near the cribs or barrels, as the vapor will ignite
or explode with a spark. Carelessness in this respect might lead to serious
When last year's crop is all used up, the crib should be swept out, and
whitewashed. A pint of crude carbolic acid should be added to every two
gallons of the whitewash, which should be applied in every nook and crevice.
Or crude carbolic acid (or carbolineum), mixed with three times as much
water, may be applied by a sprinkling can to the walls and floor. This will
kill the insects and their eggs, and will also act as a wood preservative.
State papers please copy.