6 Farmers’ Bulletin 1101. 
vegetables, etc., which may be swept from one location to another 
by a swollen stream. Even without such means of riding to safety, 
a flooded colony may not suffer extinction by drowning. The species 
has a remarkable habit of self-preservation in times of floods, for 
when rising water floods a nest, and no other way of escape is pre- 
sented, the ants may cluster together and form a compact ball. The 
immature stages cluster at the center of this mass, while the queens 
and workers form the outer portion. As the ball enlarges by the 
addition of other workers which have been struggling alone in the 
water it gradually revolves. It is kept revolving slowly by the out- 
side workers continually striving to reach the top of the ball, thus 
‘ permitting air to reach the interior. The ants in these balls disperse 
when they come into contact with a secure resting place, but they 
may float about on still water for hours. 
VARIOUS FORMS. 
As with other ants, there are several distinct forms in a colony. 
The queen is a sexually perfect female, capable of depositing eggs. 
In one colony a number of queens may be present. The males or 
drones have apparently only the function of fertilizing the queens. 
The workers, foragers of the colony, are imperfect females with no 
reproductive functions. Besides these adult forms, there are usually 
eggs and other immature stages in a nest. (Fig. 1.) 
CONTROL. 
NATURAL CONTROL NOT EFFECTIVE, 
Though sudden heavy rains, especially when combined with low 
temperatures in winter, reduce the numbers of the Argentine ant, 
it has been found that it is only a question of months before the 
normal infestation is regained. Other forms of natural control are 
of still less importance. 
HOW TO KEEP ANTS FROM TREES. 
Woglum and Neuls+ recommend the following tree-banding mix- 
ture for keeping the ants from crawling up trees: 
Finely powdered flowers of sulphur______---__ part by weight__ 1 
Commercial tree-banding sticky material ______ parts by weight__ 6 
The two ingredients are mixed together thoroughly with a wooden paddle un- 
til of a uniform color and consistency. The tree trunk should first be coated 
with melted paraffin, which will harden almost immediately. The mixture just 
1 Woglum, R. S., and Neuls, J. D. The Common Mealybug and Its Control in Califor- 
nia. U.S. Dept. Agr. Farmers’ Bul. 862. 1917. 
