CONTROL OF ARGENTINE ANT IN CALIFORNIA. 
31 
Fig. 13.— Types of ground traps: a, A small baking-powder 
tin with the edge bent to permit passage of ants; b, a special 
ground trap used in California for control about residences. 
the main runways of the ants. A small baking-powder can with 
friction cover indented in two or three places immediately beneath 
the cover to allow passage of ants would prove satisfactory. Such a 
can is being used in Louisiana. A very successful lawn trap used 
in California consists of a 
pimiento can protected by 
a special cover attached to 
a 6-inch stake. (Fig. 13.) 
A hole is made in the grass 
large enough for the can. 
The stick is then set into 
the ground until the cover 
fits firmly over the can. 
When these covers are 
painted foliage-green and 
sunk even with the grass 
they are inconspicuous. 
The lawn can be mowed or watered without destroying the sirup or 
container. 
FILLING AND DISTRIBUTING CONTAINERS 
It has been found most practical to fill the containers in the field. 
The cans or bags are prepared beforehand and taken into the orchard. 
These are arranged on 
trays as shown in figure 
14. A gallon can with 
a long spout is handy 
for filling. In each con- 
tainer three-fourths to 
one inch of sirup is used 
and this in reality aver- 
ages about 1-^ ounces. 
At first small cubes of 
sponge were used in each 
can or bag to increase 
the feeding surface. It 
was soon discovered that 
the sponges hastened 
evaporation and thick- 
ening of the sirup and were thus a disadvantage rather than an asset. 
A very satisfactory substitute for the sponge was found in excelsior and 
four or five clean strands about a foot long were folded very loosely in 
the can or preferably suspended from the top, as shown in figure 15. 
Under no circumstances should a large, heavy, compact wad of excel- 
sior be used. The advantage of the loose strands is that they furnish 
an attractive runway for the ants, reduce the likelihood of their 
Fig. 14.— A convenient type of tray for field distribution of poison 
containers, and a 1-gallon can for holding poisoned sirup. 
