The Argentine Ant as a Household Pest. 11 
cans should be sufficient to place around an ordinary city house and 
lot. If the grounds are large and if many trees are present, more 
cans should be placed out. 
From the results so far obtained, the careful preparation of the 
poisoned sirup can not be too highly emphasized. Very accurate 
balances are necessary for the weighing out of the poison and the 
tartaric acid. This is especially true when small quantities of the 
sirup are prepared. 
PLANS FOR MUNICIPAL CONTROL WORK. 
In effecting control in towns and cities it is first necessary to ascer- 
tain the extent of the infestation. This should be mapped out so that 
workmen in distributing the cans will be able to refer to the map to 
insure the covering of the entire territory. Cans may be obtained at 
wholesale at about $16 per thousand.t About 10 pounds of “ grass” 
sponges will be required per 1,000 cans. These will cost about 75 ° 
cents per pound. The sponges should be thoroughly washed and 
dried before use. When wet they may be easily torn into pieces 
about 2 by 2 inches. Using 1 gill of sirup per can,.200 pounds of 
granulated sugar will be required per 1,000 cans. The cost of the 
sodium arsenite is about 80 cents per pound, and 1 pound will be 
sufficient for 1,500 cans. Tartaric acid (crystallized) costs about 70 
cents a pound, which will be enough for 4,500 cans. From 60 to 
100 cans will be required per block, depending on the size of the 
block. The late fall, winter, and spring are the most desirable times 
in which to do this work, as in these seasons the natural food is least 
plentiful and the ants most hungry. Two men should be able to 
prepare the sirup, wash and tear up the sponges, and charge about 
2,000 cans per day and distribute about 1,000 cans per day. 
TRAPPING ANTS. 
By taking advantage of their winter colonizing habits the ants 
may be attracted in large numbers to specially prepared trap boxes, 
which may be fumigated when large numbers have gathered in these 
boxes for winter nesting. The boxes should be filled with decaying 
vegetation, the heat generated making them very attractive as 
hibernating quarters. Carbon disulphid was found to be the best 
and most economical fumigant for use in the trap boxes. It is 
hardly necessary to state that this method of control is not applicable 
to city conditions, where dry nesting quarters are very plentiful 
and the ants do not colonize to any great extent. 
1The cost figures given in this paragraph are approximately normal. Present war 
prices are probably higher for each item. 
WASHINGTON : GOVERNMENT PRINTING OFFICE : 1920 
