26 Farmers’ Bulletin 1275. 
pods, as shown by the exit holes in the pods of Figures 24 and 25. 
The weevils in large bulks of unthrashed or unshelled beans or peas 
can not be satisfactorily treated. There is only one answer to the 
often-asked question, “Is it better to store beans or peas in the pod 
or shelled?” Shell the seeds and treat 
them if you expect weevil injury. 
FUMIGATION. 
Weevils may be killed in storage by 
fumigation with carbon disulphid, car- 
bon tetrachlorid, or hydrocyanic-acid 
gas. 
CARBON DISULPHID. 
Fumigation with carbon disulphid 
(CS,) is one of the simplest remedies 
for weevils. The nature and use of 
this fumigant is discussed in Farmers 
Bulletin 799, which can be had upon 
request from the United States De- 
partment of Agriculture. Carbon di- 
sulphid is purchased as a liquid in iron 
drums or tin cans and weighs about 
104 pounds per gallon at ordinary tem- 
peratures. Upon exposure to air the 
liquid evaporates or volatilizes, form- 
ing a foul-smelling gas that is about 
twice as heavy as air. Because the gas 
is heavier than air and evaporates 
more quickly if a larger surface of the 
liquid is exposed to the air, the liquid 
should be poured out into shallow pie 
tins or similar shallow dishes and 
Vig. 25.—Pod of field pea showing 
exit hole of cowpea weevil. placed upon the top of the seeds to 
This pod was taken from a bale be fumigated. Seeds will not be in- 
of field-pea hay grown in Flor- : ; 1 oF tl li id . 
ida and indicates that even jured or polsonec 1 1e qui 1S 
field-pea hay grown only for sprinkled or poured directly upon 
eattle food may be instrumen- | T a ‘i t] t f 
tal in offsetting community co- them. n estima Ing 1eé amount O 
operation to lessen weevil in- carbon disulphid needed, the amount 
jury. Somewhat enlarged. : > 2 “ries 
of cubic space in the container in 
which the fumigation is done should always be considered—not the 
amount of space occupied by the seeds. 
If used according to directions, carbon disulphid will not injure 
the germination of thoroughly dry seeds or affect their value for 
