ants are named for their habit of excavating, tunneling and living
in wood. Two kinds are of concern--the red carpenter and the black
carpenter ant. Their habits and sizes are similar, but the latter
is by far the more common.
bees, ants are social insects. An ant colony consists of workers
and a queen. The workers are sterile, wingless females, 6-12 mm
(1/4-1/2 inch) long. The smallest residents of the colony, the workers
gather food and water to feed the colony and gnaw out wood to make
the galleries in which the colony lives.
In two to five
years, a colony with a good supply of food may form a reproductive
or dispersal generation. This generation consists of winged males
and females. Males, known as drones, are about 16 mm (5/8 inch)
long; winged females from 16 mm to 22 mm (5/8 to 7/8 inch) long.
Most drones die shortly after fertilizing the female°s eggs. The
females shed their wings immediately after mating and become full-fledged
queens. A 20 mm (3/4 inch) long, wingless ant is probably a queen
carpenter ant. The queen looks for wet, rotten wood in which to
start new a colony or join an existing one. A queen starting a new
colony lays about 30 eggs and cares for the larvae until they are
adult workers. This new generation of workers takes over the various
chores in the colony and the queen's full-time job becomes laying
is the carpenter ant's natural habitat. Carpenter ants infest live,
dead or fallen trees wherever there is some rot and moisture. They
play an important role in recycling wood in the forest. Buildings
close to a forest with rotting logs and trees are likely candidates
for carpenter ant infestations.
a water and food supply is to the nest, the faster an ant population
increases, and the greater the need to enlarge the galleries to
accommodate the colony. The process of excavation is what damages
or weakens wooden structures. Tunneling can take place inside any
piece of wood without visible signs of the process on the outside.
do not eat wood, but rather tunnel to increase nesting space. In
the forest, carpenter ants feed on sap, pollen, nectar, fruits,
and both living and dead insects. Water is an important part of
In a house
or other building, infestations may begin because of a water leak
around the chimney, roof valley, gutter, window, door frame or space
under wooden floors where there is no basement. Sill areas invite
ants, especially if soil touches the wood. Wood from new construction
provides an excellent nesting place. Kitchen and bathrooms also
often provide ample moisture for ant infestations through leaks
in water pipes or water-heating systems. Ants are often transported
indoors on firewood.
ants are nocturnal, their presence is usually only noticeable when
a colony is under stress because of lack of water, food or nesting
space, or because they are in a reproductive generation.
of large ants usually is the first sign of infestation. Coarse sawdust
is a sure sign, but it is often difficult to find the nest. At night,
turning on a light to observe ant activity around a sugary bait
that has been left out may reveal an "ant line" to and from the
nest. Sometimes the insects' activity can be heard in walls. Tapping
areas suspected of harboring nests with a hammer may produce a hollow
sound, and some excited ants may appear.
has proven to be an effective ant control. Make a 1% Boric Acid
and 20% sugar solution by thoroughly dissolving 1 teaspoon of
acid and 10 teaspoons of sugar in 2 cups of water. Soak cotton
balls in this solution and place in a small dish. Keep the cotton
from drying out for continued effectivess by covering the container
and replenishing with the boric acid solution when needed.
There is usually
no need to tear walls open to eliminate a colony unless repairs
are to be made anyway to a faulty or damaged structure. Drilling
a 6 to 9 mm (1/4 to 1/8 inch) hole into suspect areas such as walls,
sills, joists, underneath sinks, behind appliances or below outside
siding can aid in the application of insecticide to the nest if
the boric acid solution is not effective. The most effective control
is achieved when an insecticide such as an ant and roach killer
is placed in the ants' nest. If you cannot locate the nest, but
manage to leave insecticide nearby, workers may carry the poison
into the nest on their feet. Crack and crevice controls usually
take longer (if they work at all) because it takes time for workers
to carry enough insecticide into the nest to kill the colony.
There are many
other species of ants which are generally beneficial or innocuous
when outdoors, but which can become a nuisance indoors. Most of
these species can also be treated with a boric acid solution.
from the University of Maine Cooperative Extension and the Cornell
Cooperative Extension, 1999