Carpenter ants are social insects, with colonies made up of several different forms or “castes”. They are so-called carpenter ants because of their habit of chewing wood to create nest sites. They do not eat wood, like termites, but excavate it with their strong, saw-like jaws to create random galleries where they nest. They play ecosystem roles particularly by aiding in the decomposition of decaying tees. Carpenter ants belong to the subfamily Formicinae (Genus: Camponotus)

1. A PRESENTATION
ON
CARPENTER ANTS
B Y
UWAMOSE OSAIGBOKAN MARTINS
CHIEF LIBRARIAN
DEPARTMENT OF ANIMAL AND ENVIRONMENTAL BIOLOGY
FACULTY OF SCIENCE,
DELTA STATE UNIVERSITY, ABRAKA
MARCH, 2014 1

2. INTRODUCTION
Carpenter ants are social insects, with colonies made up of
several different forms or “castes”. They are called
carpenter ants because of their habit of excavating wood to
create nest sites. In contrary to what many people
think, carpenter ants do not actually eat wood like
termites, but simply nest in it. Their economic importance
as wood-destroyers exceeds that of termites in some
places. They pose a major problem to humans because of
this their habit of nesting in woods especially at home
(Hansen and Akre 1985). Carpenter ants are large ants
indigenous to many parts of the world, they are the largest
of the pest ants found in the United States
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3. Fig 2. Typical carpenter ant (worker).
Source: Google images
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Fig 1. Typical carpenter ant damage.
Source: Suiter D.R., 2012

4. IDENTIFICATION
Carpenter ants, genus Camponotus, belong to the subfamily
Formicinae. They are two pest species of primary importance, the
black carpenter ant (Camponotus pennsylvanicus) and the Florida
carpenter ant (Camponotus floridanus). Black carpenter ants are
dull black and their abdomen is covered by yellowish hairs and more
common, while the Florida carpenter ant has a deep reddish-colored
head and thorax and a shiny black abdomen (Figure 3).
The adults (Figure 4) vary in length from about 1⁄4 inch (6 mm) for a
minor worker, to 1⁄2 inch (12 mm) for a major worker, and up to
7⁄16 inch (18 mm) for winged reproductives, queens which are
usually functional, wingless are 9⁄16 inch (20 mm) long.
Camponotus workers are easily recognized by the thoracic
dorsum, which is evenly convex when viewed from the side (Hansen
and Akre. 1985).
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5. Fig 3. The two species of Carpenter ants: A. Florida Carpenter ant (Camponotus floridanus), B. Black
Carpenter ant (Camponotus pennsylvanicus)
Source: Suiter D.R., 2012
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A. B.

6. Fig. 4. Reproductives in a carpenter ant colony: A. winged female, B. queen without wings, C. male.
Source: Hansen L.D., 2005
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7. BIOLOGY
 Carpenter ants are social insects, with colonies. They become active in the
spring (March/April) and remain active through the early fall
(September/October). During the winter, ants become inactive and hibernate in
their nest to survive the cold.
 Carpenter ants are most active at night. Unlike other pest ant
species, carpenter ants create semi-permanent trails through the grass from
their nest to areas where they collect food. Movement between nest sites and
feeding sites is often facilitated by the use of these well-maintained, semi-
permanent trails (Figure 5). In the evening, ants can be seen using these trails
as they emerge from and return to their nest. Colonies may even use the same
trail in different years. Carpenter ants also follow man-made guides, such as
wall edges, when foraging (Figure 6).
 Carpenter ants feed mainly in the tops of trees where they consume the
sweet, sugar rich honeydew excreted by aphids and scale insects (in large
quantities during the spring and summer months) that are found feeding on
the tree’s sap. Solid food, including other insects and household scraps
(sweets, meat, and pet food), makes up only a small part of their diet (Suiter
D.R., 2012). 7

8. Fig. 6. Carpenter ants use well
established, semi permanent trails (blue
arrow) as they move between nest sites
and feeding sites, and will even use the
same path from one year to the next.
Source: Suiter D.R., 2012
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Figure 5. Carpenter ants may travel well over 100
feet from nest sites to feeding sites. In this figure
ants could be seen traveling 120 feet along a
permanent trail from the tree on the left (yellow
arrow) to the tree on the right (red arrow) where
they were foraging for food.
Source: Suiter D.R., 2012

9. NEST HABITS
 Carpenter ants live in colonies. A colony may contain a main nest and one or
more “satellite nests”. The main nest contains the queen, eggs, and small
larvae. A satellite nest contains pupae, mature larvae, and workers. Ants in
satellite nests are the ones that normally do structural damage to homes.
Carpenter ants establish their nest sites in wood suffering from moisture inside
and/or outside the home because damp wood is easier for the ants to chew.
Damp wood, combined with warm temperatures, also promotes the
survival, growth, and reproduction of carpenter ant colonies.
 Indoors, carpenter ants have been found nesting in moisture-damaged wood
under bathtubs, inside dishwashers, in wall voids beneath window sills, inside
hollow doors and door frames, in wood porch supports and columns, under
siding and wood shingles, and in moisture-damaged eaves.
 Outdoors, carpenter ants nests are most commonly found in hardwood trees
containing tree holes (Figure 7). In tree holes, ants find an environment that is
ecologically stable (consistent humidity and temperature) and protected from
adverse environmental conditions and natural enemies. There they chew dead
wood to create galleries for nest sites (Smith, 1965). 9

10. Fig. 7. Outdoors, the most common nest site of black carpenter ants is in hardwood trees containing
one or more tree holes.
Source: Suiter D.R., 2012
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11. MANAGEMENT OF
CARPENTER ANTS
The management of carpenter ants can be categorized
into the following:
• Eliminating carpenter ants nest
• Treating nest sites indoors
• Treating nest sites outdoors
• Control attempts when the nest cannot be found
• Prevention
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12. ELIMINATING CARPENTER ANTS NEST
The key to eliminating carpenter ant infestations is to find the
nest and remove it, either physically (e.g., by vacuum) or by
treating it with an insecticide. This is often difficult but not
impossible. The best indication of an infestation is the sawdust
that ants excavate from their tunnels. Another indication of an
infestation is sound produced by the workers as they excavate
wood to enlarge the nest. This sound often can be heard
through the infested wall. Another clue is the presence of
foraging trails, which are easiest to locate between sunset and
sunrise when the ants are most active. These foraging trails
lead away from the house to foraging sites, often in trees. If a
nest is present, ants will be seen moving up and down the
trunk as they leave from and return to the nest with food
(Figure 8). 12

13. Fig. 9. The presence of numerous carpenter ants moving up and down a tree trunk is a strong
indication of colony presence.
Source: Suiter D.R., 2012
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14. TREATING NEST SITES INDOORS
Insect nests can either be physically remove or treated
with an insecticide labeled for ant control indoors.
Insecticidal dusts and/or aerosols can be used to eliminate
carpenter ant infestations indoors. Small amounts of dusts
can be applied into voids where the ants are known to be
nesting, or are suspected of nesting and/or in voids that
they use when foraging. Dusts are airborne and as such it
is advisable to wear a protective mask when applying so
that they will not be contacted. Aerosol formulations may
also be used when indoor ant nests are visible and
accessible.
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15. TREATING NEST SITES OUTDOORS
Simply pour a water-based, liquid insecticide
directly into carpenter ant nests located in tree
holes. Use enough insecticide to thoroughly
saturate the entire nest and all ants inside. If the
nest is awkwardly positioned and difficult to reach
with a liquid spray, it may be necessary to drill a
small hole into the top of the suspected nest
location so that the liquid insecticide can be
introduced and allowed to flow downward through
the nest.
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16. CONTROL ATTEMPTS WHEN THE NEST
CANNOT BE FOUND
Often times the nest cannot be found or, if found, cannot be easily treated.
Under these circumstances, baits are used or outside is treated with a liquid
spray (perimeter treatment).
Baits are an effective means of controlling ants in some cases. Indoors use
liquid baits and baits contained in childproof, plastic bait stations; while
outdoors uses liquid and granular baits. The baits are placed in areas where
ants have been seen often next to semi-permanent trails and trees
containing nests (Figure 11).
Perimeter treatments are used as a means of keeping ants from entering
the structure. It is done by spaying the outside walls with a water
based, liquid insecticide two to three feet up and spray the ground five feet
away from each wall. The application of a liquid insecticide to the trunk of
each tree on which carpenter ants have been seen is a strategy which kills
ants moving up and down the tree trunk. Perimeter treatments should be
re-applied within a week following a heavy rain.
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17. 17
Fig. 11. Since carpenter ants rarely deviate from
their foraging trail, baits should be placed next to
the trail and as close to the suspected colony
location as possible. Baits should be delivered
from several points sources and not scattered.
Source: Suiter D.R., 2012

18. PREVENTION
Unless you change the conditions that attracted the ants, control measures will
not have a permanent effect. Homeowners should therefore take several
measures to help prevent future problems with carpenter ants.
 Since carpenter ants often nest in moisture-softened wood, prevent
dampness by ensuring that water drains away from the house and by
providing adequate ventilation in crawl spaces to help make the home a less
desirable nesting site to ants and other pests.
 Replace water-damaged wood. Keep rain gutters clean and adjust drain
spouts so water flows away from the building. Install rain gutters if they do
not already exist. If building a new home, avoid house designs with flat
roofs, which are prone to drainage problems.
 Trim tree limbs away from the structure. Foraging carpenter ants often
enter structures by bridging to roofs and siding from tree branches in
contact with these surfaces.
 Examine firewood logs before purchasing and discard any infested ones.
Store firewood off the ground, away from the house. Inspect and replace
decaying landscape timbers.
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19. CONCLUSION
Because of their nesting habits carpenter ants can
be persistent pests in and around homes. The key to
eliminating a carpenter ant infestation is to find the
nest and remove it. Look both indoors and
outdoors for carpenter ant nests, and use the most
appropriate control strategy to eliminate the
infestation. If insecticides are used they must be
used judiciously. Also, eliminate sources of excess
moisture to help make the home a less desirable
nesting site to ants and other pests.
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20. THANK YOU
FOR YOUR TIME
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