GENERAL DESCRIPTION 
Adult - The most visible ant found in and around buildings; they are
large, approximately 1 /4" to 3/4" in length. Thorax evenly rounded. Circle
of hairs at abdomen tip. (Polymorphic adults will vary in size in the
same nest.) Black, yellowish or black variegated with reddish (rusty)
brown or grayish in color. At least ten species are native to the United
States; they are found nesting in decaying wood, including lumber in buildings,
but do not eat wood; primary foods are honeydew derived from other insects,
as well as fruit, fruit juice, meat, grease, fat and dead insects. Their
thin waist consists of one petiole or "knot" which is pointed. The legs
are long and the antennae elbowed. The winged forms have four wings, the
front wings longer and larger than the hind wings. The male can be distinguished
from the female by its smaller head and protruding genitalia. Ants in
the genus Crematogasta are also called "carpenter ants". The most common
species is Lineolata (Say) which is variably colored and only about 1/8"
long. They sound like crinkling cellophane as they move about inside their
nests.
- Larva - White grub-like young found only within the nest where it
is fed and cared for by adult workers.
- Pupa - Brown in paper-like cocoon. Size of the cocoon is dependent
on the type of pupa inside-worker, female or male.
- Egg - Small, white, egg-shaped object laid singly by the queen ant
within the nest.
LENGTH OF LIFE CYCLE - Approximately 2-1/2 months or
longer. Colonies of ants mature in 2 to 6 years and normally contain 2,000
- 3,000 individuals. Swarms of 200-400 winged reproductive forms are then
produced each spring or early in the summer - they mate in the air.
HABITAT - They can be found outside or inside or any
room in a structure, particularly where food or garbage is stored, prepared
or handled. Initial nesting usually occurs in softer wood, such as decaying
logs, moist or rotted beams, structure siding, trees and wood fences,
hollow doors, window and door sills, decks, fireplaces, sill boxes, etc.
especially wherever there is or has been a source of moisture. They are
nocturnal by choice and are, therefore, best observed at night. They love
high humidity (wood or voids with over 20% moisture content), so use a
dehumidifier and repair all moisture problems.
NATURE OF INJURY - These ants carve galleries into the
damaged/soft wood (with the grain) to make their nest. They may eventually
hollow out and damage sound structural timbers. They are also a visual
annoyance as they wander in search of food, and the foraging workers have
rather large mandibles with which they can bite. Bang on the wall and
then listen for carpenter ant nests with a stethoscope.
FOOD - They do not eat wood, they only cut galleries
and create frass (wood fragments or sawdust) as they hollow out their
nests from decayed areas in your building. Workers forage for sweet food
such as honeydew, syrups, honey, jelly sugar and other sweet materials,
e.g., apples and fruit, or even garbage, dead or living insects, grease,
fat and/or meat scraps. They may travel 300 feet or more from the brood
nest to find food. Food is carried back to the nest where it is regurgitated
and used to feed the queen, larva and non-foraging workers.
HARBORAGE POINTS (Nests) - Typical carpenter ant nesting
sites are found inside branches, hollow porch columns, exposed wood beams,
floors and walls near leaking plumbing, roof areas with leaks or built-up
roofs, walls near stopped-up gutters, hollow core doors, wallboards, particularly
under sinks, toilets, dishwashers and/or windows that sweat such as storm
windows, cabinet bases, planter boxes, wood shingle roofs, firewood in
fireplaces, or in any damp or rotten structural members of a structure.
In the woods, they will be found in fallen logs, hollow trees, or around
broken limbs. Galleries are continually being carved inside timbers to
create the ever-expanding nest . As the colony numbers increase the nest
will eventually extend into dry, sound lumber. Galleries are irregular
in shape, smooth surfaced and clean; they look like they have been sand-papered.
Frass or wood fragments are carried from the nest and deposited outside.
Piles of this frass or sawdust (which can also include insect fragments,
soil particles and food residues) may often be found beneath infested
wood members and is very helpful in locating the nests. Inspections should
also be made at night using red or yellow light.
For control of carpenter ant infestation, you must locate the nest. Some
people have had success putting out sugary food and/or trays of frozen
crickets and following the ants carrying food back to their nest. If you
can remove the nest completely, no further control will be needed. Otherwise,
poison the nest with boric acid, sodium borate, silica gel or diatomaceous
earth. Install negative ion plates.
Remove and replace all damaged and wet wood and do all necessary repairs
to prevent future moisture build-up in wood. Also take precautions to
prevent access to your building, e.g., trim branches that touch or overhang
the building and remove debris on the roof..
Even if least-toxic pesticide poisons are to be used, only use them to
spot treat the nest. Never allow monthly synthetic pesticide poison applications
or allow an application of these toxic materials to the entire building.
These practices are unnecessary and very dangerous to people and pets.
Control is easily accomplished if the nests can be located. Tap the walls
and hollow doors and listen for a rustling noise in the wall, floor, woodwork
or prefabricated doors that is loud enough to hear when you place your
ear against the surface adjacent to the nest. A thorough initial inspection
should be made both indoors and outdoors to locate the colony sources.
When a nest is located, it should be treated with boric acid or other
desiccation dust, or you can completely treat the wood with sodium borate
or use baits. Install a dehumidifier.
OUTSIDE TREATMENT - Carpenter ants migrate from recently
removed trees and buildings and from rotten structural timbers, trees,
old logs, fireplace wood and similar areas to enter your building. Remove
and burn all infested wood, hollow trees, old logs, firewood, etc. and/or
treat with boric acid and/or sodium borate and fill all cavities. If your
building has with vine covered walls (which are particularly attractive
to ants), you should consider removing the vines completely. Carpenter
Ants may also use crevices in wood shingle roofs for harborage. If found,
caulk these areas completely. Prune all tree limbs and branches so that
they do not touch or overhang the building and correct all visible moisture
problems that cause wet and rotting wood. Install and properly maintain
eavestroughs and downspouts. Do not forget to install enough dehumidifiers.
Attics and crawl spaces should be inspected and spot treated or baited
and properly vented. If necessary, they may even be treated completely
with sodium borate per the label directions. Spray nests with white vinegar
and/or with enzyme cleaners.
INTERIOR WORK - Thoroughly caulk all cracks and crevices
that ants could use to migrate from wallboards and other similar areas
to their food sources. Watch for ants or the sawdust like material they
discard in building their nests. When the actual nests are located or
suspected, treat the voids with dusts, e.g. boric acid and/or sodium borate.
Nests in wall voids such as under windows may require drilling. Be sure
to reseal with a caulk or plaster any holes you make to inject boric acid,
silica gels, diatomaceous earth and/or sodium borate.
Reinfestations - Reinfestations usually indicate that more ants have
moved into the structure or that ants have not contacted earlier controls
in their foraging trips. Be sure that enough time has elapsed (at least
two weeks) to gain control before making any retreatments. Make a careful
re-examination to try to locate the nests. Look for sawdust or ants. Small
jar lids of honey or jelly or cut up crickets can attract ants so that
you may be able to follow them to the nests. Carpenter ants, however,
may not go directly to a nest but take other erratic paths. Thus, considerable
time may be required to find all of the nests. At night follow them with
a flashlight covered with red or yellow cellophane. Properly place use
either labeled commercially prepared baits or equal portions of honey
or jelly and/or peanut butter and boric acid. Place the baits out of reach
of children, pets and food. If you find ants dead by the bait, cut back
on the boric acid.
LARGE ANTS (1/2 Inch or Larger)
CARPENTER ANT CAMPONOTUS SUMMARY
There are many species of Carpenter Ants in North America; few enter
structures to forage; fewer nest in structures. But these two habits (foraging
and nesting inside) coupled with their large size and vigorous activity
make these invaders impossible to ignore. Two species claim the majority
of attention: the Black Carpenter ant of the eastern and southern United
States and the Western Carpenter ant, a particular problem in the Pacific
northwest. As their name implies, carpenter ants work and live in wood;
they do not digest it. They mate in teh air - the queen gets enough sperm
to last 10 years or more.
An important first consideration in the control of ants is to determine
whether:
- the colony is located inside the structure, or
- the colony is located outside the structure.
Indications that a colony is inside are when: ant workers
are consistently found inside over a long uninterrupted period, nest building
is observed inside (Look for wood shavings of carpenter ants, "dumping
" materials of pavement ants, etc.), the infestation is located in a high-rise
building, or inside swarming is observed.
Indications that a colony is outside are when:
ants outside can be seen coming inside.
Nesting sites outside are near the structure with an inside infestation,
(Look for mounds next to the foundation, or trees with large carpenter
ant colonies touching an infested portion of the house.)
Ants nest under slabs or swarm inside, but workers do not forage inside.
Ants inside can be "trailed" outside
Whether the colony is inside or outdoors, ants that are known to tend
honeydew-producing insects often forage inside before plant insect populations
can buildup outside. After populations of aphids, mealybugs, scale insects,
white flies and plant-hoppers become numerous (in late spring), ant colonies
nearby put a great deal of energy into tending and protecting these plant-sucking
insects. Worker ants foraging inside kitchens and basements often leave
houses at this time. They may return in dry weather seeking moisture,
but often will not be seen until the next spring. When pest control efforts
coincide with this period, it is often difficult to tell whether the pest
management procedures are effective, or whether the ants. abandoned the
structure due to natural habit.
Attend to the following general considerations in developing an ant control
plan:
Inspection
Talk to the occupants. Get all information possible from the residents.
Observe ant worker movement and plot on diagram if need be. Look for
the focus of the infestation.
To confirm observations, use traps baited with a grease and a sugar or
syrup or other ingredients suggested in The Best Control individual control
notes, e.g., peanut butter and cookies.
Inside: Inspect holes and cracks where workers enter,
old or new moisture stains, food accumulations, e.g., dry pet food, activity
near appliances. e. g., dishwasher and washing machines, under bath tubs,
showers, in drawers, corresponding areas in adjoining room or rooms above
and below activity.
Outside: Inspect for workers behind vines, shrubs,
other plants near house, expansion joints, slabs, patio blocks, bricks,
boards, plant pots, under and inside wooden columns and pillars, outside
door and window frames, window wells, penetrations of house wall by telephone
wires, air conditioning refrigerant pipes, trees that harbor colonies
and provide access to houses by overhanging limbs that touch or even scratch
shingles; water meters and storm drain inspection manholes. Inspect plants
for ants tending aphids, mealybugs. Note: Leaf-cutter ants will not defoliate
tall plants, e.g., roses, fruit trees, etc. if loosely-wadded sheep wool
is tied around the stem; ants don't like to cross it and it is almost
totally effective.
Habitat Alteration
- Caulk wall penetrations and mortar masonry cracks. Wall penetrations
include utility lines, air conditioning, refrigerant pipes, phone lines,
etc.
- Tighten door and window frames. Sprinkle talcum powder and/or Gold
Bond® powders.
- Repair water leaks.
- Trim shrubbery away from house.
- Remove firewood that is stacked close to buildings; boards, stones,
etc. that encourage nesting; screen openings in hollow pillars, columns,
and ventilators.
- Control ant-tended aphids and mealybugs with horticultural pesticides,
such as oils or soaps.
Control
Conduct a thorough inspection. Install negative ion plates. Spray and/or
mop with borax.
Consider the species when choosing bait. Use baits with stomach poisons,
e.g., boric acid, or with insect growth regulators. Baits are excellent
in critical areas, e.g., computer or hospital rooms. Do not spray or dust
around baits. Never store baits or bait materials where they can be contaminated
with any other odors, especially fumes of pesticides. Ants and other insects
can detect minute amounts of foreign or repellent chemicals and will avoid
chalk lines.
Vacuum and then carefully caulk/seal all cracks and crevices where a
nest is suspected.
Spray nests with white vinegar, enzyme cleaners or sprinkle them with
baby powder or crushed chalk.
Develop a specific pest management plan. Where large outside areas need
treatment, e.g., fire ant problems; do not treat with pesticide poisons
as an extension of a yard problem. Ants use two methods to establish trails
- phermones and structural guideline orientation - investigate both. Properly
install negative ion plates; use borax laundry powder and/or spray with
white vinegar, enzyme cleaners and/or soapy water. Practice proper sanitation,
structural alterations and moisture source reduction.
Follow-up - Reinspect in two weeks; ask all occupants if they have seen
any remaining troublesome ant problems. Remember, pesticide poison treatments
can repel ants and make them active in other areas. Colonies with multiple
queens may break up into several colonies, so do not use synthetic pesticide
poisons for this reason, and because they are very dangerous to you, the
occupants and the environment. Use IGR's, baits, vacuums and, if absolutely
necessary, you may apply spot treatments of silica aerogel and/or boric
acid dusts as a last resort.
Carpenter ants are usually a symptom of a water leak or moisture problem
because they usually nest in wood that remains wet. Check for leaks around
windows and doors, plumbing fixtures and under shingles and make necessary
repairs. Keep foods in tightly sealed containers or in the refrigerator.
Most ants prefer sweets, protein, fats or grease. Practice good sanitation.
Avoid leaving dirty dishes or food particles where they are accessible
to ants. Caulk cracks and crevices in building foundations. Remove rotted
lumber, firewood and stumps inside crawls and from around buildings. Prune
tree branches that overhand or touch buildings to prevent carpenter ants
from coming inside. |