• Two nodes 
• Worker size: 1/8 to 1/4 inch (3 to 7 mm) 
• Uneven thorax o 12 antennal segments, 3-segmented club
• One pair of spines on thorax 
• Color varies from brown to black to reddish

ID Tip. The pedicel (nodes) attaches to the top of the gaster instead of the middle. The abdomen, when viewed from above, is shaped like a heart. Acrobat ants get their name from the habit of holding their abdomens above their thorax - like acrobats - when the workers or colony are disturbed. 
Feeding Habits. Acrobat ants feed on a wide variety of foods including both sweets and proteins. Inside structures, acrobat ants will feed on household foods and show a preference for sweets. 
Key Inspection Tips. Inspecting for colonies of acrobat ants is similar to an inspection for carpenter ants. When workers are found foraging indoors, the first place to inspect is the exterior of the structure.
Outside: Inspect the building's foundation for trails of workers. Workers may also be observed trailing on tree and shrub branches that brush against the structure. Wires and cables are another avenue for worker ants trailing onto the structure. The eaves of structures should be inspected for ant trails or workers entering cracks in the soffits. Signs of excess moisture should be noted along the fascia boards and under soffits. Such signs include warped boards, peeling paint and fungi on the surface of wood. Suspect areas in the soffits will need to be inspected more closely using a ladder. 
Inside: Acrobat ant colonies are most often found in areas where water leaks have occurred. It is important to ask the customer if they are aware of any water leaks in the building within the past several years. These areas should be inspected first. A moisture meter is helpful in locating areas of high moisture. Firewood stored inside should also be checked for ant colonies. Termite-damaged wood should be probed for the presence of colonies, particularly in basements and crawlspaces. 
When acrobat ants infest wood damaged by other insects, they often clear out bits of dirt and dead insects. This debris is often deposited in piles in visible areas and indicates the presence of an ant colony. Bits of foam in window sills or on door thresholds may indicate ants infesting foam insulation. Professionals may occasionally mistake these bits as evidence of powderpost beetles. Care should be taken to confirm the actual type of insect present. 
Contributing Conditions. Dead wood and wood debris, as well as areas - both indoors and outdoors - that contain a high level of moisture content should be checked for ant activity. Any water leaks that are present must be corrected. Clogged gutters must be cleared. Tree and shrub branches which brush against the structure should be cut back. As many cracks and holes as possible in the building's exterior should be sealed.

Control Solution

• One node 
• Worker size: 1/8 to 1/4 inch (3.5 to 7 mm) 
• Uneven thorax 
• 12 antennal segments, no club 
• Head and thorax are reddish 
• Abdomen and legs are dark 
• Circle of hairs present at tip of abdomen

I.D. Tip: This ant builds large nests that are usually easy to spot. Upon a quick glance, this ant resembles red and black species of carpenter ants, but the Allegheny mound ant is easily distinguished by its uneven thorax. 
Feeding Habits. This ant is omnivorous and feeds on a wide variety of foods, including both dead and live insects. It will tend homopterous insects (aphids, mealybugs and scales) that live in trees and shrubs for the "honeydew" they produce. They protect these insects from predators. 
Key Inspection Tips. The Allegheny mound ant is found throughout the upper Midwest to the New England states and south to Georgia. These ants build large mounds, sometimes mistaken to be those of fire ants, which has led to "fire ant scares" in some northern states.
This ant does not enter structures, but can be found living in lawns of houses and commercial structures that are adjacent to fields or wooded areas. The Allegheny mound ant causes no real harm, but it will bite if the mound is disturbed. For this reason, many homeowners may wish to have the mounds on their property treated. Finding the mounds built by Allegheny mound ants is usually quite easy. Customers most often will already have identified where the mounds are located. An inspection of the property should be completed to determine if any newly formed mounds are present that may not be readily visible. Other than lawns, mounds may also be located in hidden areas under shrubs or ground-covering ivy in landscape beds. 
Single colonies may consist of several closely-situated mounds tied together into a larger, supercolony. The workers excavate tremendous amounts of soil in digging their underground galleries. This excavated soil forms the mounds characteristic of this ant. It is not uncommon to find mounds up to 3 feet in diameter in undisturbed areas, such as fields or wooded areas. Homeowners, however, will rarely allow mounds on their property to grow larger than 1 foot in diameter before seeking to control them. 
Contributing Conditions. The condition which contributes most to the presence of the Allegheny mound ant is lawns and landscaping around homes and other structures that are located next to fields or wooded areas.
Often, little can be done to change this factor. A field of weeds can be mowed regularly which may keep the numbers of colonies down; however, this may not be possible if the adjacent field is not owned by you.

Control Solution

INTRODUCTION. This species, which is native to Argentina and Brazil, was probably introduced at New Orleans via coffee ships from Brazil before 1891. Argentine ants are found in the southern states and in California, with isolated infestations in Illinois, Maryland, Missouri, Oregon, and Washington.

RECOGNITION. Workers monomorphic, about 1/16" (2.2-2.6 mm) long; queens about 1/8-1/4" (4-6 mm) in length. Body varies from light to dark brown. Antenna 12-segmented, without a club. Thorax lacks spines, profile unevenly rounded. Pedicel 1-segmented. Gaster with anal opening slitlike, lacking circlet of hairs. Stinger absent but can bite on provocation. Workers emit a stale greasy or musty odor when crushed.

SIMILAR GROUPS. (1) Odorous house ant (Tapinoma sessile) has pedicel/node nearly hidden by front edge of abdomen/gaster, emit a sweetish rotten coconut odor when crushed. (2) Crazy ant (Paratrechina longicornis) with legs very long in relation to body size, antenna! scape (1st segment) at least 2 times head length, anal opening circular, surrounded by circlet of hairs. (3) Other small dark ants with 2 nodes/segments in pedicel and/or thorax with 1 or more spines/teeth on upper surface.

BIOLOGY. Colonies are located in moist situations near a food source. They include a few hundred to several thousand workers and many queens; numbers fluctuate seasonally. In the autumn, outside colonies join together to form huge overwintering nests. Development time (egg to adult) is 33-141 days, averaging 74 days. Winged female reproductives are rarely seen because mating takes place inside the nest. The workers are very aggressive and usually eliminate other ant species and some other insects from the area. However, ants from different Argentine ant colonies are friendly and do not fight.

HABITS. Inside, these ants usually nest near a moisture source such as water pipes, sinks, potted plants, etc. The workers follow regular trails when foraging, and winged queens can sometimes be found among trailing workers. Workers commonly tend honeydew-producing insects. The preferred foods are sweets such as sugars and syrup but they will feed on almost every kind of food including meats, eggs, oil, fats, etc.

Outside, Argentine ants typically live in shallow nests located in moist situations such as under boards and stones, beneath plants, along sidewalks, etc. This ant prefers sweets such as honeydew' fruit juices, and plant secretions, but also steals seeds, attacks poultry chicks, disrupts bee hives, etc. Their habit of crawling over everything including refuse, sewage, sputum, carrion, etc. affords them the opportunity to transport the causative disease organisms for dysentery, etc.

Argentine ants invade buildings in large numbers when conditions outside are either too wet or too dry for them to live. Also, a decrease in their honeydew supply sends them indoors seeking sweets. They will readily trail along tree and shrub branches, as well as utility lines/wires to gain entrance.

CONTROL. Location of the nest(s) and its treatment with a residual insecticide is ideal; try following ants back from the food source. Be sure to pull back the grass from around foundation walls and the edges of concrete sidewalks and driveways because these ants will trail below the grassline where they are not visible. Baiting and use of insecticide dust in the voids of the outside ground-floor walls is the preferred treatment. Outside perimeter barrier treatments are essential and must be well maintained.

Control Solution

• Two nodes 
• Worker size: 1/6 to 1/8 inch (1.5 to 3.5 mm) 
• Uneven shape of thorax 
• 12 antennal segments, 3-segmented club 
• One pair of spines on thorax 
• Light brown to dark reddish brown

ID Tip. Big-headed ants have two distinct sizes of workers - major workers and minor workers. Major workers are easily recognized by having very large heads in proportion to their bodies. 
Feeding Habits. Big-headed ants feed on live and dead insects, seeds and the honeydew produced by homopterous insects (e.g., aphids, mealybugs and scale insects). In houses, they seem to prefer protein foods, such as meats and peanut butter, but will also feed on greases and sweets, such as fruit juices. 
Key Inspection Tips. Big-headed ants forage in trails of a few up to hundreds of workers. These trails can usually be located without too much difficulty along sidewalks and foundations and up the extension sides of buildings. 
Inside: Big-headed ants trail along baseboards and are commonly found foraging under the edges of carpets. When these ants are found indoors, an attempt should be made to follow the foraging workers back to the site where the colony is located. If the ants are entering and exiting from under the wall, an inspection outside along the foundation is necessary to see if the ants inside are coming from a colony located outdoors. 
Outside: Grass or other vegetation should be pulled or raked away from the foundation of the building and along driveways and sidewalks. Colonies are often found in the soil beneath the grass next to the building's foundation, and this is one of the first areas that should be checked. Big-headed ants also will nest and forage under the grass line along sidewalks and patios where they cannot be seen. Mulch should be raked back from the bases of trees and shrubs to check for ant colonies. Items in contact with the soil, such as logs, stones, firewood and other debris, should be lifted to check for colonies. 
Contributing Conditions. As with most ants, moisture is a limiting factor in the survival of bigheaded ants. If conditions exist which result in excess moisture (e.g., poor foundation drainage or water leaks), they should be corrected. As many cracks in the exterior walls as possible need to be sealed.
If possible, a vegetation-free border should be installed around the base of the foundation to make the area less attractive to ants and to make inspections of the foundation easier. This vegetation-free border should contain gravel or small stones over plastic sheeting and not bark chips or mulch. Items under which big-headed ants could nest should be removed. These items include boards, bricks, stones and logs. Firewood should be stored off the ground and as far from the structure as possible.

Control Solution

• One node 
• Workers size: 1/5 to 1/2 inch (9 to 13 mm) 
• Evenly rounded thorax 
• 12 Antennal segments 
• The head, thorax and petiole is yellowish-red to red, abdomen is black 
• Body covered with long, yellowish hairs

I.D. Tip. This species of carpenter ant, in the subgenus Myrmothrix, can be a serious structural pest in Florida and other parts of the extreme southeast U.S. 
Feeding Habits. Carpenter ants feed on a wide variety of foods. A favored food is the sweet honeydew produced by aphids, mealybugs and scales. Carpenter ant food preferences can also change over the course of the seasons. 
During the spring when the larvae are growing, most of the foraging targets protein foods. A switch is made to carbohydrates (e.g., honeydew) during the summer when adult workers are at their most numerous. 
Key Inspection Tips. This ant is very opportunistic in selecting its nesting sites. One of the more common nesting sites is under rocks, logs, landscape timbers and debris lying on the ground. Dead tree branches, rotting stumps and moist timbers in buildings are other nesting sites. Piles of trash or other debris seem to be highly preferred for nesting, particularly in developed areas where trees are less available. 
Inside homes, nests may be discovered most often in wall voids, behind dishwashers and under insulation in attics. Florida carpenter ant satellite colonies were also found in the following unusual sites: air conditioning units, switch outlet boxes in the wall, a ceiling light fixture, a water cooler, book shelves, electronic games, wall clocks, potted plants, debris in rain gutters, water beds, spa filters, a steam iron, a VCR, clothes pins stored in a milk jug and the rubber seal of a refrigerator.
When dealing with infestations of Florida carpenter ants, any item lying in contact with the ground could harbor a colony. This is particularly true of piles of items, such as lumber, bricks, firewood, or trash. Items lying on top of mulch in landscape beds provides good nesting sites for colonies of this species. 
Contributing Conditions. Moisture and dead wood are the two primary conditions present in and around structures that contribute to carpenter ant infestations. Structures which are located in wooded areas or on wooded lots have plenty of both and, therefore, have more potential for problems.
Structures without many trees on the property, however, can also experience infestations. This is particularly true if the structure contains sites with excessive moisture, thus creating an ideal area for carpenter ants. 
If conditions which are contributing to the carpenter ant infestation are not corrected, the carpenter ant problem may not be eliminated.

Control Solution

• One node 
• Worker size: 1/8 to 1/3 inch (3.5 to 9 mm) 
• Evenly rounded thorax 
• 12 antennal segments 
• The body of this species is mostly black with the rear portion of the thorax, the petiole and the legs dark red.

I.D. Tip. This species of carpenter ant occurs in the northern United States from the East Coast to the West Coast. The ant is reportedly the second most common structure-infesting species in Minnesota. 
Feeding Habits. Carpenter ants feed on a wide variety of foods, including dead insects. A favored food is the sweet honeydew produced by aphids, mealybugs and scales. Carpenter ant food preferences can also change over the course of the seasons. During the spring when the larvae are growing, most of the foraging targets protein foods. A switch is made to carbohydrates (e.g., honeydew) during the summer when adult workers are at their most numerous. 
Key Inspection Tips. This ant nests primarily in wood and can be found in the same wooded areas as the black carpenter ant, C. pennsylvanicus, and the western carpenter ant, C. modoc. It is rarely seen in deforested areas, such as much of North Dakota. Its colonies are mediumsized, numbering from several thousand to as much as 12,000. 
Carpenter ants get their name from their habit of hollowing out wood to build a nest. They require a moist or humid environment in which to establish a colony. They usually prefer to nest in moist or damaged wood, but they will nest in dry, sound wood. In structures, they are commonly found where water has leaked and soaked the surrounding wood. Leaks often occur around plumbing in kitchens and bathrooms, in roofs, and the soffits where gutters are absent or are poorly installed. Poorly ventilated attics and crawlspaces create an ideal, humid environment that is attractive to carpenter ants. 
Inside buildings, carpenter ants readily nest in any moist or humid, hollow void. In fact, a great many of the colonies found inside buildings will be satellite colonies and these will usually be associated with voids rather than be inside wood. Colonies can be found living in voids which are seemingly dry and satellite colonies are frequently discovered under and behind insulation in attics, basements and crawlspaces. 
Contributing Conditions. Moisture and dead wood are the two primary conditions present in and around structures that contribute to carpenter ant infestations. Structures which are located in wooded areas or on wooded lots have plenty of both and, therefore, have more potential for problems.
Structures without many trees on the property, however, can also experience infestations. This is particularly true if the structure contains sites with excessive moisture. If conditions which are contributing to the carpenter ant infestation are not corrected, the carpenter ant problem may not be eliminated or will return soon.

Control Solution

• One node 
• Evenly rounded thorax 
• 12 antennal segments 
• Worker size: 1/5 to 1/2 inch (9 to 13 mm)
• Abdomen has long yellow hairs, and circle of hairs at tip

I.D. Tip: This ant is recognized by its black body and dark red legs. 
Feeding Habits. Carpenter ants feed on a wide variety of foods, including dead insects. A favored food is the sweet honeydew produced by aphids, mealybugs and scales. Carpenter ant food preferences can also change over the course of the seasons. During the spring when the larvae are growing, most of the foraging targets protein foods. A switch is made to carbohydrates (e.g., honeydew) during the summer when adult workers are at their most numerous.
Key Inspection Tips. Camponotus modoc is the most common structure-infesting ant along the west coast, especially the Pacific Northwest. Colonies may be quite large with up to 50,000 workers. A mature colony of C. modoc along the Pacific Coast may have up to 20 or more satellite colonies which is a major factor that makes this species difficult to control. Foraging activity for C. modoc in the Northwest occurs between April and October with May to September serving as the peak foraging period. 
C. modoc has been shown to make distinct, visible trails in lawns and landscaping areas from the main colony to satellite colonies. These trails are often well worn and up to two inches wide. Trails are also not necessarily above the ground as subterranean trails have been discovered by gardeners and termite control professionals when they dig in the soil. Typically, these subterranean trails follow tree roots several inches below the soil surface, but trails have been discovered as deep as 4 feet along tree roots. 
Main colonies usually occur outdoors in stumps, living trees, landscape timbers, etc. with up to 20 or more satellite colonies located in other trees, landscape timbers and voids and wood timbers in buildings. This species infests more structures than any other Camponotus species in the Pacific Northwest. 
Contributing Conditions. Moisture and dead wood are the two primary conditions present in and around structures which contribute to carpenter ant infestations. Structures which are located in wooded areas or on wooded lots have plenty of both and, therefore, have more potential for problems with carpenter ants. 
Structures without many trees on the property, however, can also experience carpenter ant infestations. This is particularly true if the structure contains numerous sites with excessive moisture. If conditions which are contributing to the carpenter ant infestation are not corrected, the carpenter ant problem may not be eliminated or will return soon. Correcting these conditions is the most important step in the long-term management of carpenter ant infestations.

Control Solution

INTRODUCTION. The black carpenter ant, Camponotus pennsylvanicus (DeGreer), is a native species and the common species in the east. Camponotus modoc Wheeler is the common western species. These ants get their common name from their habit of hollowing out galleries in pieces of wood for nesting purposes. This nesting habit can result in structural damage. Carpenter ants are found throughout the United States.

RECOGNITION. Workers polymorphic, large (1/8-1/2" or 3.5-13 mm) but vary greatly in size; queens about 112-518" (13-17 mm) long. Color black, combinations of red and black, or completely red or brown. Antenna 12-segmented, without a club. Thorax lacks spines, profile evenly rounded on upper side. Peel 1-segmented. Gassier with anal opening round, surrounded by circlet of hairs. Stinger absent. Workers capable of emitting a strong formic acid odor.

Camponotus pennsylvanicus with workers about 1/4-1/2" (6-13 mm) long and completely black except top of gaster with long, pale yellowish hairs pressed against its surface. Camponotus modoc with workers about 1/4-1/2" (5-11 mm) long, dull black with reddish legs and with golden hairs covering abdomen. Queens up to 5/8+" (17+ mm) long. Other species black, various combinations of red and black, or completely red or brown. Although carpenter ants do not sting, their bites can be quite painful, especially when they inject formic acid into the wound.

SIMILAR GROUPS. (1) Dark field (Formica spp.), larger yellow (Acanthomyops interjectus), and Allegheny mound (F. exsectoides) ants have profile of thorax not evenly rounded, with distinct impression(s); in addition dark field ants with front and hind margins of node steeply or equally sloped. (2) Velvety tree ants (Liometopum spp.) lack circular anal opening surrounded by circlet of hairs. (3) Other medium to large dark ants with 2-segmented pedicel.

DAMAGE. The only external indication of infestation other than the presence of workers and/or swarmers is the appearance of small openings or windows on the surface of the wood. Through these, the workers expel debris which consists of sawdust-like shavings and/or fragments of insulation and insect body parts. The accumulation of such debris below such holes is a good indication of an infestation.

Inside, the galleries follow the softer spring wood with numerous connections through the harder/dark summer wood. The gallery walls are smooth, with a sand-papered appearance. The active galleries are kept clean of debris.

They prefer to attack wood softened by fungus and are often associated with moisture problems.

BIOLOGY. Black carpenter ant colonies are of moderate size, usually containing over 3,000 workers (up to 10-15,000 including satellite nests) when maturity is reached in about 3 to 6 years. The typical western carpenter ant (C. modoc) mature colony contains about 10-20,000 workers, with large colonies having up to 100,000 workers. Developmental time (egg to adult) for workers takes at least 60 days. Workers are polymorphic, with majors, minors and intermediates present. There is usually only one functional, wingless queen per colony. Swarmers are not produced until the colony is more than 2 years old, usually 3.5-4 years old for C. pennsylvanicus and often 6-10 years old for C. modoc. Swarmers appear from May until August in the east and from February through June in the west.

HABITS. Most carpenter ant species establish their first nest in decayed wood and later expand or enlarge this into sound wood. Inside, nests are located in wood (preferably softened by fungus rot), in insulation, and/or in wall voids. Workers are a nuisance when out searching for food but are destructive to timbers utilized for nesting activities. Outside, nests are typically located in rotting fence posts, stumps, old firewood, dead portions of standing trees, and under stones or fallen logs.

The presence of a carpenter ant nest is sometimes indicated by a rustling sound coming from wall voids or from wood where the colony is located. Otherwise, the emergence of swarmers indoors may be the first indication of an indoor colony.

Carpenter ants feed primarily on insect honeydew, plant and fruit juices, insects, and other arthropods. Inside, they will also feed on sweets, eggs, meats, cakes, and grease.

The workers forage for distances of up to 300 feet (91.4m) from the nest. They typically enter buildings around door and window frames, eaves, plumbing and utility lines, and shrub and tree branches in contact with the building. Although some workers are active during the day, most activity is from dusk till dawn, with peak activity between 10 pm and 2 am. The trail between the parent and satellite nest is usually about 1/4-13/16" (6-20 mm) wide and is kept clear of vegetation and debris. It usually follows contours but typically will cut across lawns.

CONTROL. The first step is to determine if the ants present are merely foraging inside or if there is a nest inside. The best indication of a nest is the presence of sawdust piles containing insect body parts. Another indication is the sound produced as the workers remove wood to expand the nest. Outside, check around the building's perimeter for foraging trails, especially in the direction of trees and shrubs; easiest to locate between sunset and sunrise when the ants are most active.

The second step is to locate any inside nests. Look for sawdust piles with insect body parts. Listen for ant sounds mentioned above; listening devices are helpful. Gently tap with a screwdriver, etc. all exposed wood such as floor joists, sill plates, roof rafters, etc. and listen for sound changes; nest cavities give a hollow or dull ring. Check suspicious areas with a knife blade which will readily penetrate infested wood. Be sure to check crawl spaces, basements, and attics. Carpenter ants have a network of trails they follow throughout a structure and often use the tops of electrical Wires and water pipes, so be sure to check where these are. A moisture meter can be helpful in locating areas of higher moisture in which the ants prefer to locate their initial nests.

The third step is to determine if the inside colony is a parent or satellite colony. Inspect and search. Detection of a trail directs one to the parent colony. For effective control, it is imperative to locate and eliminate the parent colony.

Once the colony or colonies are located, they should be treated directly with an appropriately labeled pesticide. Inside, this may involve drilling wall voids and applying dust and/or drilling wood members and pressure injection. Barrier treatment is effective in preventing entry, with wettable powder and microencapsulated formulations working best. All branches of trees and shrubs in contact with the building must be trimmed back. Be sure to check where electrical and water lines enter the building and caulk any gaps. Sometimes treating the bottom 3-6 feet (1-2 m) of tree trunks and/or utility poles is helpful.

Control Solution

• One node 
• Evenly rounded thorax 
• 12 antennal segments
• Thorax is red, while rest of this ant's body is black 
• Worker size: 1/4 to 1/2 inch (7 to 13 mm)

I.D. Tip. The thorax of this ant is red with the rest of the body and legs black. 
Feeding Habits. Carpenter ants feed on a wide variety of foods, including dead insects. A favored food is the sweet honeydew produced by aphids, mealybugs and scales. Carpenter and food preferences can also change over the course of the seasons. During the spring when the larvae are growing, most of the foraging targets protein foods. A switch is made to carbohydrates (e.g., honeydew) during the summer when adult workers are at their most numerous. 
Key Inspection Tips. This species occurs from the West Coast east to the Dakotas and Alberta, Canada and south to Mexico. This species is a serious structural pest, second only to C. modoc in Washington state. Colonies can be very large, up to 100,000 workers, and will have multiple queens. It will nest in sound wood but prefers fungus- or moisturedamaged wood. Its nesting habits outdoors are varied, ranging from dead trees and rotting stumps to beneath rocks and logs on the forest floor. It has also been observed to nest in the heartwood of living trees. 
When looking for carpenter ants, structural guidelines should remain a focus of the inspection. Edges of sidewalks, fences, decks and fascia boards will often have ants trailing along them. By following the structural guidelines as they connect with one another, the trail may be more easily followed.
Signs of high moisture content in structural wood - water stains, peeling paint, fungi, etc. - can be an indicator of areas where carpenter ants are present. A moisture meter is handy in determining where leaks may be present or have occurred in the past. Hollow porch columns are common sites for carpenter ant activity. Foraging workers on tree trunks may indicate a colony located somewhere up in the tree. Tree limbs which brush against the walls or the roof of the structure should be inspected for workers trailing onto the structure. 
Contributing Conditions. Moisture and dead wood are the two primary conditions present in and around structures which contribute to carpenter ant infestations. Structures which are located in wooded areas or on wooded lots have plenty of both and, therefore, have more potential for problems with carpenter ants. Structures without many trees on the property, however, can also experience carpenter ant infestations. This is particularly true if the structure contains numerous sites with excessive moisture. If conditions which are contributing to the carpenter ant infestation are not corrected, the carpenter ant problem may not be eliminated or will return soon. Correcting these conditions is the most important step in the long-term management of carpenter ant infestations.

Control Solution

• One node 
• One size of worker, 1/10 inch (2 to 2.5 mm) 
• Uneven thorax o Scape (first segment of antenna) is shorter than the head 
• Brown to very dark brown in coloration

ID Tips. Eyes are relatively large in comparison to the size of the head. 
Feeding Habits. The cornfield ant is particularly fond of sweets, but it will readily feed on both live and dead insects. Indoors, this ant will be attracted to sweet foods, but may feed on literally any crumbs that fall to the floor. 
Key Inspection Tips. Numerous mounds in lawns are a common sight in those areas where cornfield ants are abundant. The nests are very common in fields and in and around homes, where they may be found between bricks in the walk, beneath rocks, in cracks in the pavement, in the lawn, etc. Extended colonies may occur where a group of mounds are interconnected by foraging trails. Nests may also be formed in landscape mulch or in the soil beneath objects lying on the ground.
This ant will nest in walls and floors in association with water leaks and poor drainage and ventilation, hence its nickname of "moisture ant." It is particularly prevalent around bathtubs and showers where leaks are present or have occurred. Most often, such colonies are associated with fungus damage and decay; therefore, the moisture condition has likely been present for many months. Moisture-damaged wood is often hollow, creating galleries similar to those of carpenter ants. Old termite and carpenter ant galleries may occasionally be occupied by this species. The cornfield ant will construct tubes or nests of soil inside walls. In a few cases, colonies will locate in the soil beneath slabs and enter through expansion joints and other cracks in the slab. Such subslab nests occur more frequently in commercial buildings. Small piles of soil displaced from beneath the slam may be seen on top of slabs under which colonies are located. Nests under slabs outside, such as sidewalks and patios, may also be determined by piles of displaced soil. 
Outside: The cornfield ant readily establishes strong trails that are easy to find. The trails will typically follow structural guidelines, such as the edges of sidewalks. Colonies should be easy to locate by the piles of displaced soil associated with soil nests. Any item in contact with the ground should be inspected underneath for colonies. 
Contributing Conditions. Outdoors, contributing conditions are negligible with this ant. Exterior cracks should be sealed to help prevent foragers from entering. Inside, water leaks must be repaired and the surrounding void and wet wood thoroughly dried. In many cases, correcting the moisture conditions results in the ants vacating the structure. Severely damaged wood should be replaced. Steps should be taken to improve the ventilation in poorly ventilated crawlspaces to make these areas less attractive to ants.

Control Solution

• One node 
• One size worker: 1/8 inch (3 to 3.5 mm) 
• Uneven thorax o 12 antennal segments, no antennal club 
• Circle of hairs on tip of abdomen 
• Dark brown to black coloration

ID Tip. Extremely long legs and antennae. The first segment of antennae is more than twice as long as the head. Crazy ants get their name from their habit of running about very erratically with no apparent sense of direction. 
Feeding Habits. Crazy ants feed on a variety of foods, other insects, grease and sweets. 
Key Inspection Tips. Trails of crazy ants will usually be quite visible on walkways, foundations, and the sides of buildings. Once a trail of ants is found, workers carrying bits of food or whose abdomens appear swollen with food or water will usually be returning to the colony. The trail should be followed in the direction in which these workers are heading. 
Outside: Any object lying on the ground, such as lumber, stones, or trash, is a potential nesting site. Piles of any item are especially coveted by this ant (and other ants), particularly items in shaded, damp areas. Landscape mulch should be moved away from the building foundation and the base of trees and shrubs to check for ant colonies. Crazy ants forage long distances from the colony so a thorough inspection of the entire property is necessary. Branches of trees and shrubs brushing against the building should be checked for trails of foraging ants. The sides and edges of soffits on homes are often a site for foraging crazy ants. Nests in soffits and attics are not out of the question, especially if the attic is poorly ventilated and humid or excess moisture is evident in the soffits. Crazy ants have also been observed to live in gravel and underneath wood on the flat roofs of commercial buildings. When infestations occur on the upper floors of tall buildings, the roof should be inspected.
Inside: Crazy ants will nest in wall voids and in the soil of potted plants and atriums. The workers will forage along baseboards both above and below the edge of carpets. When crazy ants are observed foraging indoors, an attempt should be made to follow the trail to the point where the ants enter under a wall or through a crack (e.g., under a doorway). If ants are observed entering under a wall, the foundation and wall outside that area may reveal ants entering from a colony located outdoors.
Contributing Conditions. If conditions exist which result in excess moisture they should be corrected. Branches of trees and shrubs need to be pruned away from the structure's roof and walls. As many cracks in the exterior walls as possible need to be sealed. Items under which crazy ants could nest should be removed. 
If possible, a vegetation-free border should be installed around the base of the foundation to make the area less attractive to ants and to make inspection easier. This vegetation-free border should contain gravel or small stones and not bark chips or mulch. Mulch and bark chips hold moisture, creating an ideal nesting site for ants.

Control Solution

• One node 
• One size worker, typically 3/8 inch (10 mm) 
• Uneven thorax 
• Color varies from black, brown, tan, reddish, or red and black 
• Circle of hairs on tip of abdomen

ID Tip. Closely resemble carpenter ant in appearance, however, field ants have an uneven thorax.
Feeding Habits. The ants feed on a wide variety of materials, such as live and dead insects and the honeydew produced by aphids, mealybugs and scales. 
Key Inspection Tips. Various species of Formica "field ants" are found throughout much of the United States. These ants are a particular problem in midwestern and northern states. Field ants are common around structures, but will only occasionally be seen indoors. 
Foraging workers are quite common, however, on patios, sidewalks, decks and the foundations of buildings where they can be mistaken for carpenter ants. When a homeowner complains of seeing black ants on porches outside, correct identification is necessary to determine if the ants are either field ants or carpenter ants. If field ants are involved, the lawn and landscaped areas should be targeted for inspection to locate the mounds and colonies of this ant. 
The mounds built by field ants in lawns are often low in profile, rarely reaching far above the top of the grass. A slow walk across the lawn is necessary to find these mounds. Items such as logs, firewood, bricks, debris and stones must be overturned and inspected for colonies underneath. Mounds are sometimes located at the base of shrubs in landscaped areas and have also been found in thick layers of landscape mulch. 
Field ants are soil nesters that construct medium-sized mounds of about 8 to 10 inches (20 to 25 cm) in diameter in open fields and vacant lots. Mounds can also be found in lawns surrounding homes and other buildings. These ants will also commonly nest under items, such as rocks, patio blocks, landscape timbers and firewood piles. It is not uncommon to see a small amount of displaced soil along side a flagstone of landscape timber. Lifting the item may reveal a colony underneath. 
Field ant workers forage actively and are commonly seen crawling around on porches, patios and wood decks. Foraging trails are loose, meaning that foragers are spaced further apart, making the trail more difficult to detect. Once a food source is found, numerous foragers are recruited to exploit the food. 
Contributing Conditions. Where possible, items under which this ant might live, such as stones, logs, debris, and lumber should be removed. Firewood should be stored off the ground and as far from the structure as possible. Leaf litter should be removed. Further, steps should be taken to make sure that layers of mulch in landscape beds around the structure do not build up to more than 2 inches (5 cm) thick.

Control Solution

COMMON NAME: Fire Ants SCIENTIFIC NAME: Solenopsis spp. CLASS/ORDER/FAMILY: Insecta/Hymenoptera/Formicidae METAMORPHOSIS: Complete

INTRODUCTION. These ants get their common name from their ability to inflict especially painful bites and stings. The two most important species are the southern fire ant (Solenopsis xyloni McCook) and the red imported fire ant (Solenopsis invicta Buren). The southern fire ant is a native species and ranges from California to southern South Carolina to northern Florida. The red imported fire ant is from central Brazil and is found in the southeastern United States, from Virginia through Texas.

RECOGNITION. Workers polymorphic, about 1/16-1/4" (1.6-6 mm) long; queens average 1/4" (6.6 mm) long. Head and thorax yellowish red and abdomen black; reproductives darker. Antenna 10-segmented, with 2-segmented club. Thorax lacks spines, profile unevenly rounded. Pedicel 2-segmented. Stinger extruded in most alcohol-collected specimens; readily inflict painful stings.

Characteristics of the mandible and petiole (1^st node of pedicel) will separate these 2 species. The mandible of S. xyloni has 3 distinct teeth on its inner/biting surface whereas, those of S. invicta have 4 teeth and the petiole of S. xyloni has a ventral tooth near the node's attachment to the thorax whereas, S. invicta lacks such a tooth.

SIMILAR GROUPS. (1) Fire ant (Solenopsis geminate) with ridge on lower front margin of mesothorax having 1 or more teeth, 1^st node in profile with rear margin almost straight. (2) Little black ant (Monomorium minimum) with antenna 12-segmented, club 3-segmented. (3) Acrobat (Crematogaster spp.), big-headed (Pheidole megacephala), harvester (Pogonomyrmex spp.), and pavement (Tetramorium caespitum) ants have spines on upper surface of thorax; in addition acrobat ants with heart-shaped abdomen and pedicel attached to upper surface of abdomen, big-headed ants with soldier with head very large and 3-segmented antennal club, harvester ants with underside of head with a brush of long bristles (coarse hairs/setae called psammophores), and pavement ants with head and thorax covered with distinct ridges. (4) Other small dark ants have 1-segmented pedicel.

BIOLOGY. For the red imported fire ant, single-queen mounds usually number 30-100/acre (0.4ha) with typically 80,000 but up to 250,000 individuals per colony. Multiqueened colonies may number 200-700/acre (0.4ha) but contain fewer individuals per colony, and there is less fighting between the colonies. Typical mounds are rounded, being up to 18" (48 cm) high and 24+" (61+ cm) in diameter, each with several tunnels just under the soil surface extending out several feet. A queen in a large colony is capable of producing her own weight in eggs each day or about 1,500 or more. Developmental time (egg to adult) for workers ranges from 22-38 days. A mature colony can produce as many as 4,500 swarmers during the year, with 6-8 mating flights occurring between spring and fall. Mating flights usually begin about 10 am, 1-2 days following a rain if it is warm (about 75 degrees F / 24 degrees C), sunny, and not very windy. Minor workers live 30-60 days, intermediates (medial) 60-90 days, and majors 90-180 days or longer. Queens live 2-6 years. Males die shortly after mating.

Typical mounds of the southern fire ant are flattened and irregular, covering 2-4 sq ft (0.17-0.37 sq m). Swarms occur from May through October in the afternoon to early evening of warm days. Developmental time can require as few as 44 days. Its biology has not been thoroughly studied.

HABITS. Fire ants are typically ground-nesting ants. However, the southern fire ant will sometimes nest in the wood or masonry of buildings, especially in areas near the soil or warmth such as fireplace hearths. When the southern fire ant nests outside near a house, it is usually in the vicinity of the kitchen. Outside nests are usually situated under stones or other covering objects, or in the soil at the base of a tree or shrub, or in clumps of grass.

The red imported fire ant typically nests outside. Each colony has its own territory, and there is usually no movement between colonies. However, they will sometimes nest in areas of exposed soil within buildings such as bath traps. They also have the habit of building outside nests adjacent to foundation walls. They are commonly introduced into new areas via potted or balled shrubs and trees.

Fire ants are attracted to electrical junction boxes of traffic signals, air conditioners, etc. When they mass around the electrical contact points, they cause the equipment to malfunction. They will also nest in gas and water meter boxes and then follow the pipes into the building.

Fire ants prefer food with a high protein content but will feed on almost anything, plant or animal. The southern fire ant has been known to remove insulation from phone and electrical wires, and to gnaw on clothing, especially if soiled. They usually feed on seeds, insects, young tree bark, honeydew and other sweets, preferring oily meats and nuts.

Red imported fire ants are particularly destructive to vegetation. Workers forage in established trails.

CONTROL. Fire ant control is difficult. It usually requires repeated applications of liquid or granular residuals to eliminate the colony. Particularly effective with a single application are residual aerosols applied under high pressure (160 psi) with a long injection probe.

Although baits are slower acting, they are effective. Baits containing only a stomach poison require several applications each season to control newly emerging workers when the queen(s) is/was not killed, and new colonies. Baits containing only an insect growth regulator can provide year-long control with 1 or 2 applications in the residential situation when followed in 7-10 days with a liquid residual application to kill the active foragers. Newer baits containing avermectin,, which acts as both an insect growth regulator and slow-acting stomach poison, give good control without liquid application.

Control Solution

• One node 
• One size worker: 1/32 inch (1.5 mm) 
• Uneven thorax 
• 12 antennal segments, no antennal club 
• Head and thorax are dark, abdomen and legs are pale

ID Tip. This ant has a translucent abdomen, hence the name ghost ant. 
Feeding Habits. Indoors, ghost ants show a preference for sweets. They are commonly found inside packages of candy, sugar and similar foods in kitchen pantries. 
Key Inspection Tips. These ants are very small so careful inspection is essential. Inside: Foraging ghost ants are often found trailing inside under the edge of carpet. When these ants are found indoors, an attempt must be made to follow the foraging workers back to the site where the colony is located. Ghost ants are frequently found foraging inside kitchen cabinets and bathroom vanities. The first cabinets to inspect are those containing food products. Boxed and bagged items containing sweets, especially those stored at the back of the cabinet, should be inspected first. Ghost ants seem to have a high need for moisture so they are commonly seen around sinks, toilets and bathrooms. Pay attention to areas where water is available. Ghost ants readily live inside wall voids and homeowners often report seeing workers trailing out of electric outlet plates, particularly in kitchens and bathrooms.
Outside: Mulch, grass and other vegetation should be pulled away from the foundation of the building and along porches and sidewalks. Ghost ant colonies are often found in the soil beneath the grass next to the building's foundation and under heavy vegetation lying against the base of tree trunks. The exterior walls of the building around entryways, such as doors and windows, often reveal trails of ghost ants. Ghost ants will readily trail down the branches of trees and shrubs onto the structure and through cracks around the eaves and soffits. These ants will nest in the debris trapped in the crotches of trees, in hollows in trees, at the base of palm fronds, and also in hollowed out branches of shrubs. A screwdriver can be used to stir up debris in the crotches of trees. 
Contributing Conditions. As with most ants, moisture is a limiting factor in the survival of ghost ants. Conditions which result in excess moisture, such as poor foundation drainage, water leaks, or sprinklers directed against the foundation, should be corrected. As many cracks in the exterior walls as possible need to be sealed. If possible, a vegetation-free border should be installed around the base of the foundation to make the area less attractive to ants and to make inspections of the foundation easier. This vegetation-free border would contain gravel or small stones and not bark chips or mulch. Mulch and bark chips hold moisture, creating potential nesting sites for ants. Branches of trees and shrubs which touch the structure should be trimmed back away from the structure. Items under which ghost ants could nest should be removed. These items include boards, bricks, stones, logs and debris. Firewood should be stored off the ground and as far from the structure as possible.

Control Solution

• One node 
• One size of worker, 1/4 inch (7mm)
• 12 antennal segments 
• Antennal club gradually enlarges to tip 
• Has circle of hairs at tip of abdomen
• Yellow-orange in color

ID Tip. Workers give off a citronella or lemon-like odor when crushed. This ant has very small eyes.
Feeding Habits. These ants feed on the honeydew gathered from aphids and mealybugs. 
Key Inspection Tips. This ant is a minor pest inside structures except during the spring and summer when the winged reproductives (swarmers) emerge into buildings. The "citronella ant" is a soil-nesting ant that constructs nests in soil under items, such as logs, rocks, patio blocks, porches and sometimes concrete patios. This ant is often found by termite control professionals as they dig trenches in preparation for treating the soil next to the foundation. Colonies are also common in open areas of soil, especially in crawlspaces. Large colonies have been observed in the soil of crawlspaces under houses, under concrete slabs, and along the foundations outside buildings. The citronella ant also will nest in rotting wood, such as logs and firewood, which has been stored on the ground too long. It has been found living in old termite-damaged wood that is moist. Because these ants feed exclusively on subterranean homopterous insects (aphids and mealybugs) and are most active at night, foragers will rarely be seen by homeowners inside. Foraging activity occurs under the soil along plant roots where the aphids and mealybugs are found. 
If citronella ant swarmers or workers are found inside a building, time should not be wasted inspecting for colonies located inside the structure. Colonies are most likely to be found along the foundation both on the outside and on the inside if a crawlspace is present. If the ants are nesting under a concrete slab, soil excavated by the ants is usually present along the sides or on top of the slab indicating the colony's location. In addition to inspecting along the foundation, an inspection of the entire property is necessary. Outlying colonies can serve as sources for colonies becoming established next to or under the foundation. Items on the ground, such as rocks, logs, landscaping timbers, etc. should be lifted to check underneath. 
Contributing Conditions. Environmental conditions are not as important for controlling infestations of citronella ants as they are for other ants. However, establishing a vegetation-free zone along the foundation of the structure may be helpful in preventing colonies from nesting next to the foundation. Items under which ants could nest, such as stones and logs, should be removed. Firewood should be stored off the ground and as far from the structure as possible. Sealing cracks in the slab foundation can stop swarmers from entering the building.

Control Solution

• Two nodes 
• One size worker, 1/16 inch (2 mm) 
• Uneven thorax 
• Thorax has no spines 
• 12 antennal segments 
• Club segmented in 3 parts 
• Black color

ID Tip. The little black ant, not surprisingly, is a very small, black ant. This ant is closely related to the Pharaoh ant and looks just like it except for its black coloration.
Feeding Habits. The natural food of little black ants is the honeydew produced by homopterous insects (e.g., aphids, mealybugs, and scales) and sweet secretions produced by plants. Indoors, little black ants feed on sweets, meats, grease, bread, oils, cornmeal and fruit juices. 
Key Inspection Tips. Within its range, the little black ant is common in wooded areas and can be a frequent invader of homes and other buildings. Outdoors: The little black ant nests in the soil under items, such as rocks, logs or debris. It will also build nests in open areas of soil in lawns and in landscape mulch. The nests in the ground are characterized by small craters of very fine soil. Colonies have been found under the bark of trees, in debris trapped in the crotches of trees, in wood damaged by termites, in firewood piles and within stacks of bricks and stones. When inspecting for foraging little black ants, grass, vegetation and/or mulch should be pulled away from the foundation of the building and along driveways and sidewalks. 
Any item in contact with the soil such as logs, stones, etc. could harbor a colony. Sprinkler heads also may be a site to find a small colony. Little black ant colonies are most often associated with dead wood or piles of items like bricks and stones. Trails for workers often originate up tree trunks from some dead limb or tree hole. In such cases, accessing the colony may be difficult.
Inside: Little black ant colonies or individual trails can be found in wall voids, cabinet voids, under the edge of carpets, and in the voids of masonry, such as brick or stone veneer on the outside of the structure. 
When ants are found living indoors, an attempt should be made to follow the foraging workers back to the site where the colony is located. If the ants are entering and exiting from under the wall, they may be originating from outside along the foundation or from tree branches touching the building.
Contributing Conditions. As many cracks in the exterior walls as possible need to be sealed. Items under which little black ants could nest should be removed. Firewood should be stored off the ground and as far from the structure as possible. Tree and shrub branches should be trimmed away from the building. Dead tree limbs should be removed.

Control Solution

INTRODUCTION. The pungent, "rotten-coconutlike" odor given off when this ant is crushed gives it its name. It is a native species and is found throughout the United States.

RECOGNITION. Workers monomorphic, about 1/16-1/8" (2.4-3.25 mm) long. Body brown to black. Antenna 12-segmented, without a club. Thorax lacks spines, profile unevenly rounded. Pedicel 1-segmented, with small node/segment hidden/concealed from view from above by base of gaster. Gaster with anal opening slitlike, lacking circlet of hairs. Stinger absent. Workers emit a disagreeable, rotten, coconut-like odor.

SIMILAR GROUPS. (1) Ghost ant (Tapinoma melanocephalum) with head and thorax dark but abdomen and legs pale. (2) Argentine (Iridomyrmex humilis), crazy (Paratrechina longicornis), pyramid (Conomyrma insana), and dark field (Formica spp.) ants have node visible, not hidden by gaster; in addition, pyramid ants with thorax with single tooth on upper surface, field and crazy ants with circular anal opening surrounded by circlet of hairs and crazy ants additionally with antenna! scape (1st segment) at least twice head length and very long legs in relation to body size. (3) Other small dark ants have 2-segmented pedicel and/or lack rotten coconut odor when crushed.

BIOLOGY. Colonies may be composed of several hundred to 100,000 ants. There are usually many queens in a colony. Developmental time (egg to adult) is 34-83 days, varying with temperature during summer months, and up to 6-7 months during the winter. Colonies typically produce 4-5 generations a year. Although they probably mate both inside and outside the nest, the first swarmers appear from May to mid-July. The workers and queens live for several years. Individuals from different colonies are not hostile to one another and workers normally move along trails.

HABITS. Inside, these ants usually construct their nests in wall voids especially around hot water pipes and heaters, in crevices around sinks, cupboards, etc. These ants prefer sweets but also eat foods with high protein content and grease such as meats and cheese.

Outside, they are often found in the nest of larger ants, in exposed soil, but mostly under objects. Workers feed on insects, seek honeydew and plant secretions, and even feed on seeds. They are extremely fond of honeydew and attend such honeydew-excreting insects as plantlice (aphids), scale insects, mealybugs, etc. They are most likely to enter buildings when their honeydew supply is reduced such as during rainy weather or with leaf fall in the autumn.

When workers are alarmed, they run around in an erratic manner with their gasters/abdomens raised up.

CONTROL. Location of the nest(s) is crucial and can often be accomplished by following the trail of foraging workers back from the food source. Use of boric acid dust in the voids of outside ground-floor walls and infested interior walls along with barrier treatment is effective. Baiting is often required.

Control Solution

RECOGNITION. Workers monomorphic, about 1/16-1/8" (2.5-4 mm) long; queens about 3/8" (8 mm) long. Body light brown to black with paler legs and antennae. Head and thorax furrowed/grooved with parallel lines. Antenna 12-segmented, with 3-segmented club. Thorax with pair of small spines on upper back part, profile unevenly rounded. Pedicel 2-segmented Stinger present.

Swarmers can be distinguished from other ant swarmers by the presence of fine furrows/grooves on their head and thorax, similar to those of the workers.

SIMILAR GROUPS. (1) Harvester ants (Pogonomyrmex spp.) have underside of head with a brush of long bristles (coarse hairs/setae). (2) Acrobat ants (Crematogaster spp.) with pedicel attached to upper surface of abdomen (gaster), gaster heart-shaped. (3) Other small dark ants with only 1 node/segment in pedicel or if with 2 nodes, then thorax lacks spines on upper surface.

BIOLOGY. Very little work has been done on this ant. Colonies are moderately large to large, averaging 3-4,000 ants and several queens. Developmental time varies from 36 to 63 days. Winged reproductives appear outside primarily in June and July, but may emerge anytime inside including during the winter months. Workers have been shown to be an intermediate host of the poultry tapeworms Raillietina tetragona (Molin) and R. echinobothrida (Mednin).

HABITS. Inside, pavement ants will occasionally nest in walls, in insulation, and under floors. The most likely place is in ground-level masonry walls of the foundation and especially near some heat source in the winter. They often follow pipes which come through slabs for access to upper floors of buildings.

Outside, these ants typically nest under stones, in cracks in pavement, and next to buildings. They enter buildings through cracks in the slab and walls, slab expansion joints, and the natural openings of buildings. Although not aggressive, workers can bite and sting.

These ants feed on almost anything including insects, honeydew, seeds, plant sap, and household foods such as meats, nuts, cheese, honey, and bread, but show a preference for meats and grease. They forage in trails, and for distances of up to 30 feet (9 m).

CONTROL. Location of the nest(s) and its treatment with a residual is ideal; try following ants back from the food source. Dust in the voids of outside ground-floor walls, treatment of cracks in the slab with a residual, and barrier treatment is the control. The direct injection with an appropriately labeled high-pressure aerosol (160 psi) into the entrance/exit opening in the crack or expansion joint of a concrete floor is extremely effective. Baiting may be necessary.

Control Solution