The farmer and mechanic. [volume] (Raleigh, N.C.) 18??-19??, 1912-06-18
THE rOUND-BUILDING
PRAIRIE ANT.
A Most Interesting Description OF
This Industrious Little Insect
and Its Carefully Planned
Prairie Nest.
CBy GEORGE A. DEAN)

part Of the Western States, n traV-
elcr's attention is frequently Drawn
to the g~raVel-coVered mounds thal
skirt the railways and wagon roads.
Located in the center of cleared circu-
lar areas, they stand out prominently,
breaking the grassy surface. these
pounds dot the slopes Of raVlneS, the
banks Of streams and hooks and flats
between cliffs and ridges.
They occur along Travelled streets
and sidewalks. IN corrals and IN door
yards. They are present in fields OF
wheat and alfalfa, in spite Of the
plowing and disking. hey possessed
the prairie before the farmer came
and they remain in spite OF his oper-
atoms. The ant whose Industry has
made these mounds, with their clean
swept d~ooryardS. clingS tenaciOuSly TO
the house which it has built and. SO
often as h roof is destroyed, labor
iously rebuilds it.
The nests are various sizes and
heights, ranging from nine to twenty
four inches. The clearing surround
ing the mound is level. absolutely de-
void Of vegetation, and uSually has
the mound exactly in the center. The
size Of the clearing ranges from nine
to twenty feet and IN n instance
extended for fOrty-five feet.
The ants cannot tolerate the pres
ence OF vegetation near their mounds
and the workers clear it away by use
of their well-adapted mandibles. They
doubtless find that vegetation Is an
obstacle to their going and coming;
that it affords concealment to their
enemies: retains moisture after a rain.
thus favorinR the growth Of injurious
fungi; that it's roots penetrate the
chambers Of their nests and. decay
ing. form passagewayS for the en-
trance Of water.
The dexterity and ease with which
the workers handle the pebbles where
with they cover their homes is a
source of constant interest and sur
prise. A worker will seize a pebble
with outstretched mandibles and,
with head elevated. holding it we'll to
the front. carry it ove the rough sur
face to the very top of the mound
without one stopping to rest. In no
case does one worker help another
that happens to have Undertaken too
heavy a load. We have seen such
individuals struggling vainly at the
base while their comrades pass I'M
co~ncernedly up and dOwn all about
them.
In many of the mounds the ants
20 and come through one opening.
in others they have two or three III
~passageways. and in one exception
ally large mound the occupants la
eight openings, These gateWays are
usually about one-third from the base
to the summit Of the mound. At
night or on the approach of a rain
Storm, the openings are closed with
material similar to that of which the
mountaineering is composed. During
the summer the ants begin to close
them shortly before sunset and open
them between eight and nine o'clock
In the morning. So perfect is their
mr. ri 49, -, 49,
nation does not really show where
the openings hav been. The force of
workers that does the night closing
is small. but when a storm is rapidly
approaching. the numbe is greatly
increased that the work may be quick
ly completed. In the morning as soon
as the gates are opened, the working
force is out and busily engaged. II
returns to the nest shortly before moor
and remains inside until the hotties
part of the day is past, then they come
out and work until evening. Or
cool. cloudy days the midday retur1
to the nest is omitted n the force
continues in the field during tn,
whole dav. The morning and moor
hours are probably employed in car
ing FOR and charging the interior o
the nest.
The interior of the mound is honey
combed with chambers and galleries
The chambers vary from one to thre
inches in diameter and from one-hal
to one inch in height. The connect
ing galleries have a uniform diamete
Of about three-eights of an inch. Seal
ed and unSealed StoreroOms file
with seeds occur throughout tn
nest. Larvae, pupR and young AM
occupy many of the chambers
Seeds Of various kinds are carrie
by the workers into the nest. TIL
hulls are torn off, carried out an
dumped at one side Of the clearin
and the plump. sound seeds store
away in the storerooms.
The Misunderstanding prairie ar
shows three distinct classes Of indiyiC
uals-the queens fertile females
males and worker (sterile females
Queens and males form a compars
lively small portion of the colon
while the worker in a nest have bee
known to number 10000.
Although these ants are larger thu