more. Above ground, sharply defined foraging trails sometimes 
extend hundreds of feet to the plants under attack. Ants move in 
procession along these trails, each carrying a fragment of leaf or 
other material to the nest. These fragments, which may be several 
times the size of the ants carrying them, are borne upright over 
the head like a parasol. 
The ants do not eat the foliage which they remove from plants. 
Instead, they cut it up into small fragments, shape it into small 
pellets, and carry it into their underground chambers. Here it is 
placed upon so-called gardens where it serves as a medium for the 
growth of a fungus. It is this fungus which serves as the food of 
the colony. During summer most of the foliage is brought into the 
nest during the night; whereas, during fall, winter and spring 
most of it is brought in during the day, unless it is too cold or 
wet. 
Winged males and females appear during May and June and 
fly from the colony and mate. Mated females lose their wings and 
dig into the soil where they establish nests. Here they become the 
queens of new colonies. 
A pelleted bait has given good control when scattered over por- 
tions of nests where excavation mounds are concentrated (567). 
The reader should consult Agricultural Handbook 331 for details 
on the control method. 
The Allegheny mound ant, Formica exsectoides Forel, is a 
serious pest of young white pines, red pines, Scotch pines, red 
cedars, and spruces in the Eastern and Northeastern States. It 
nests in the ground and constructs mounds which may be up to 
4 feet in height and 6 feet across. In forested areas, these mounds 
are most often found in openings or along the edges of stands. 
All vegetation, excepting large trees, may be destroyed in an area 
40 to 50 feet in diameter around a mound. Trees from 2 to 15 
years old are especially susceptible to attack. Damage may be 
severe in forest plantations. The adult ant is about 3 to 6 mm. 
long. The head is reddish brown and about as wide as long; the 
thorax is reddish brown and feathered; the anal region is reddish 
and surrounded by a fringe of hairs; and the legs are sometimes 
brownish or dark red. 
The Allegheny mound ant does not feed on trees or other vege- 
tation. Its food consists of living and dead insects and honeydew 
excreted by various species of sucking insects. It appears that the 
only reason it attacks vegetation is to kill it to keep it from shad- 
ing the mounds. Trees are killed by the injection of formic acid 
into their tissues. Apparently this results in the coagulation of 
cell contents and the prevention of downward movement of foods 
in the inner bark (590). 
The life history of the Allegheny mound ant is not too well 
understood, but it is known to forage for food from April to Sep- 
tember and to spend the winter in its nest. There are several 
generations per year and both queens and workers are known to 
live for several years. 
Crematogaster cerasi (Fitch) occurs from southern Canada to 
Georgia. Its nests are found in the ground, in rotting stumps, 
logs, or branches, and in empty nuts on the ground. Nests also 
may be found in various parts of houses such as the roof, siding, 
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