It is difficult to rate the top five ant species in the United States without dividing the country into regions. The regional lists included here were compiled by surveys of Terminix technical specialists around the country and other pest management professionals. Other published surveys were also consulted.
1. Black Carpenter Ant, Camponotus pennsylvanicus
2. Pavement Ant, Tetramorium caespitum
3. Larger Yellow (Citronella) Ant, Acanthomyops interjectus
4. Little Black Ant, Monomorium minimum
Review: Alates of Hypoponera punctatissima have been reported several times in commercial buildings in Massachusetts and New York where they land on and sting people. The ants are carried north from Florida in the soil of tropical plants.
1. Black Carpenter Ant, Camponotus pennsylvanicus
2. Pavement Ant, Tetramorium caespitum
3. Cornfield Ant, Lasius alienus
4. Odorous House Ant, Tapinoma sessile
5. Larger Yellow (Citronella) Ant, Acanthomyops interjectus
Review: Richard Cooper of Cooper Pest Control notes that in New Jersey, T. caespitum and L. alienus are both significant pests in commercial structures. In residences, L. alienus is seldom seen, but T. caespitum is an important pest next to C. pennsylvanicus. T. sessile is increasingly seen in New Jersey residences and is proving to be difficult to control. Sara Pettingill and Jerry Bukovsky of Terminix note the Pharaoh ant, Monomorium pharaonis, is second in importance to C. pennsylvanicus in Virginia. Pettingill also lists acrobat ants, Crematogaster spp. and T. sessile as top five pest species in Virginia. Chris Anfinsen, also of Terminix, reports M. pharaonis and T. sessile as top five pests behind C. pennsylvanicus and T. caespitum in central Pennsylvania.
1. Argentine Ant, Linepithema humile
2. Red Imported Fire Ant, Solenopsis invicta
3. Black Carpenter Ant, Camponotus pennsylvanicus
4. Odorous House Ant, Tapinoma sessile
5. Crazy Ant, Paratrechina longicornis
Review: Acrobat ants, Crematogaster spp. and the pavement ant, Tetramorium caespitum, are top five pests of structures in East Tennessee (in addition to L. humile, C. pennsylvanicus and T. sessile), according to Jim Chase of Terminix.
1. Crazy Ant, Paratrechina longicornis
2. Ghost Ant, Tapinoma melanocephalum
3. Florida Carpenter Ant, Camponotus floridanus
4. Pharaoh Ant, Monomorium pharaonis
5. Red Imported Fire Ant, Solenopsis invicta
Review: The above list was supplied by Dr. John Mangold and Chris Graham of Terminix. A survey by Klotz et al. (1995) analyzed samples provided by PCOs and found the same species listed above as major pests. Their findings, however, showed C. floridanus, P. longicornis and S. invicta to be the top three species. Dr. Mangold reports the carpenter ant, C. tortuganus, to be significant in Central Florida, while often seeing the carpenter ant, C. planatus, in Bradenton and Sarasota.
Vail et al. (1994) list the black carpenter ant, C. pennsylvanicus and the Argentine ant, Linepithema humile, as major pests in northern Florida. This paper also notes that the big-headed ant, Pheidole megacephala, can establish large extended colonies in some neighborhoods in Central Florida. Acrobat ants, Crematogaster spp. and Monomorium floricola, are also reported as infrequent but minor structural invaders. A survey by Bieman and Wojcik (1990) confirms these results.
1. White-Footed Ant, Technomyrmex albipes
2.Ghost Ant, Tapinoma melanocephalum
3. Florida Carpenter Ant, Camponotus floridanus, C. tortuganus
4. Red Imported Fire Ant, Solenopsis invicta
5. Crazy Ant, Paratrechina longicornis
Review: Klotz et al. (1995) and Bieman and Wojcik (1990) list the same ants as major pests except T. albipes. This species has become a serious pest since these surveys were completed. Vail et al. (1994) report the robust crazy ant, Paratrechina bourbonica, is a major pest in South Florida. Ann Russell of Terminix confirms the observation that the big-headed ant, Pheidole megacephala, is a significant pest in many parts of this region. Brachymyrmex spp. alates become pests in South Florida by flying to swimming pools by the hundreds. The little fire ant, Wasmannia auropunctata, is widely spread in South Florida but is a minor pest encountered most often outdoors.
1. Black Carpenter Ant, Camponotus pennsylvanicus
2. Carpenter Ant, Camponotus herculeanus
3. Pavement Ant, Tetramorium caespitum
4. Odorous House Ant, Tapinoma sessile
5. Larger Yellow (Citronella) Ant, Acanthomyops interjectus
Review: C. herculeanus is reportedly the second most common carpenter ant pest species in Minnesota (Hansen 1995). Dr. Mike Potter of the University of Kentucky reports T. sessile is an increasingly important and difficult-to-control species in Kentucky. He also notes infestations of Pharaoh ants, Monomorium pharaonis, are not uncommon in that state. Potter also reports several species of field ants of the genus Formica are common yard pests in the state of Kentucky and are often identified incorrectly as carpenter ants. Cameron Renn of Terminix lists M. pharaonis and acrobat ants, Crematogaster spp., among his top five in Ohio and Michigan.
Jim Billings of Terminix lists the cornfield ant, Lasius alienus, and the little black ant, Monomorium minimum, as important pest species in Illinois.
1. Odorous House Ant, Tapinoma sessile
2. Red Imported Fire Ant, Solenopsisinvicta
3. Acrobat Ants, Crematogaster spp.
4. Little Black Ant, Monomorium minimum
5. Pharaoh Ant, Monomorium pharaonis
Review: David Pence of Terminix lists the Argentine ant, Linepithema humile, as a top pest, but it is more evident further east in Tennessee and into Mississippi and Alabama. T. sessile is the predominant pest. This author has found a number of carpenter ant species, Camponotus, in this region, but they are infrequent invaders despite their common presence outdoors around homes. He has also found the small honey ant, Prenolepis imparis, and big-headed ants, Pheidole spp., inside structures on a number of occasions. S. invicta is a recent newcomer to West Tennessee and Central and Northern Arkansas within the past decade and is increasingly becoming a serious pest.
1. Red Imported Fire Ant, Solenopsisinvicta
2. Pharaoh Ant, Monomorium pharaonis
3. Crazy Ant, Paratrechina longicornis
4. Carpenter Ants, Camponotus pennsylvanicus, C. ferrugineus
5. Little Black Ant, Monomorium minimum
Review: Like Florida, Texas has a wide diversity of ant species. The Argentine ant, Linepithema humile, may be encountered in parts of the state, particularly in and around Dallas-Fort Worth, according to Mike Kilpatrick of Terminix. From Central to West Texas, harvester ants, Pogonomyrmex spp., may be found damaging lawns. Field ants of the genus Formica are also common in yards and landscaping where they may be confused with carpenter ants. In the Houston area, big-headed ants, Pheidole spp., are sometimes found inside structures. In Central Texas from San Antonio north through Waco, the Texas leaf cutter ant, Atta texana, may be encountered as a serious threat to trees and shrubs in landscape beds.
1. Pavement Ant, Tetramorium caespitum
2. Harvester Ants, Pogonomyrmex spp.
3. Southern Fire Ant, Solenopsis xyloni
4. Crazy Ant, Paratrechina longicornis
5. Argentine Ant, Linepithema humile
Review: Kyle Jaber of Terminix reports in New Mexico that carpenter ants, Camponotus spp., are a primary pest with T. caespitum and Pogonomyrmex spp. He says that the odorous house ant, Tapinoma sessile, is a common pest and the Pharaoh ant, Monomorium pharaonis, is a minor pest. He has seen one confirmed case of P. longicornis in the Albuquerque area.
In Tucson, Ariz., Doug Seemann of University Pest Control notes that big-headed ants, Pheidole spp., T. sessile and the ghost ant, Tapinoma melanocephalum, have invaded homes there. Eradication programs are in effect for the red imported fire ant, Solenopsis invicta, in Yuma. He notes that carpenter ants, Camponotus spp., are generally pests at higher elevations in Arizona. Steve Jenschke of Terminix also reports the little black ant, Monomorium minimum, to be a pest in Phoenix. In Las Vegas, L. humile is the predominate pest species and T. caespitum is the second most important according to Mary Lou Seely of Terminix.
1. Carpenter Ant, Camponotus modoc
2. Carpenter Ant, Camponotus vicinus
3. Odorous House Ant, Tapinoma sessile
4. Pavement Ant, Tetramorium caespitum
5. Field Ants, Formica spp.
Review: Lonnie Anderson of Terminix and Dr. Laurel Hansen of Spokane Community Falls College both list "moisture" ants of the genera Lasius and Acanthomyops as common structural pests. Three to four species of Lasius are associated with nest-building in moist areas associated with leaks in homes. Lonnie Anderson of Terminix also reports the Pharaoh ant, Monomorium pharaonis and the ghost ant, Tapinoma melanocephalum, as pest species encountered in this region. Dr. Hansen also mentions the small carpenter ant species, C. essigi, as a commonly encountered structural invader. The pine tree ant, Liometopum luctuosum, has been reported invading homes in Idaho.
1. Argentine Ant, Linepithema humile
2. Velvety Tree Ant, Liometopum occidentale
3. California (Southern) Fire Ant, Solenopsisxyloni
4. Carpenter Ant, Camponotus modoc
5. Odorous House Ant, Tapinoma sessile
Review: According to Lonnie Anderson the Argentine ant is overwhelmingly the most pervasive pest of structures. C. modoc is common at higher elevations but not in the valleys. He also reports the ghost ant, Tapinoma melonocephalum, has been found in Redding and Eureka, Calif. A survey by Knight and Rust (1990) showed Camponotus spp, L. humile and T. sessile to be the top three pest ants in Northern California.
1. Argentine Ant, Linepithema humile
2. Harvester Ant, Pogonomyrmex spp.
3. California (Southern) Fire Ant, Solenopsis xyloni
4. Pharaoh Ant, Monomorium pharaonis
5. Red Imported Fire Ant, Solenopsisinvicta
Review: Dr. Hanif Gulmahamad of Terminix notes more than 90 percent of ant calls in Southern California are for Argentine ants. S. invicta has recently become established in the state and is expanding its range. He also notes the velvety tree ant, Liometopum occidentale, and odorous house ant, Tapinoma sessile, are common invaders in some areas. Knight and Rust (1990) found L. humile to be the predominant pest, followed by S. xyloni.
1. White-Footed Ant, Technomyrmex albipes
2. Carpenter Ant, Camponotus variegatus
3. Tropical Fire Ant, Solenopsis geminata
4. Ghost Ant, Tapinoma melanocephalum
5. Glaber Ant, Ochetellus glaber
Review: This list was provided by Dr. Niel Reimer, Hawaii Department of Agriculture. He notes that all of these species are found throughout the islands except for O. glaber, which is confined to Oahu. The Argentine ant, Linepithema humile, is found on Oahu at higher elevations and the big-headed ant, Pheidole megacephala, is widespread outdoors but is an infrequent invader of buildings. Two species unique to Hawaii as pest ants are the long-legged ant, Anoplolepis gracillipes and the "tiny yellow house ant," Plagiolepis alluaudi.
TOP U.S. PESTS. As these lists demonstrate, the most important pest species may vary greatly depending on the location. Across the northern U.S., the species of most importance would be two carpenter ant species, Camponotus pennsylvanicus and C. modoc, and the pavement ant, Tetramorium caespitum. In the Southeast, the red imported fire ant, Solenopsis invicta; the crazy ant, Paratrechina longicorni; and the Argentine ant, Linepithema humile, are the predominant pests. In the Southwest and West, the Argentine ant and the southern fire ant, Solenopsis xyloni, are the most important.
To determine the top five pest ant species in the United States, each would need to be rated by the breadth of its geographical distribution and its inclination to invade structures. Still, arguments could be made to place certain species back on the list, such as the crazy ant and the carpenter ant, C. modoc. The following would be the author’s top five. These are not arranged by importance as such determination would be nearly impossible:
1. Black Carpenter Ant, Camponotus pennsylvanicus
2. Pavement Ant, Tetramorium caespitum
3. Red Imported Fire Ant, Solenopsisinvicta
4. Argentine Ant, Linepithema humile
5. Odorous House Ant, Tapinoma sessile
It would be interesting to complete a national survey of structure-infesting ants. Such a survey should focus on those ants actually collected from inside buildings. The survey would be of most value if samples were collected each month by each participant over several years. The author may undertake such a study in the future and may call upon many of you for assistance.
Editor’s note: The author lists his acknowledgments and references at www.pctonline.com.
The author is manager of technical services for Terminix International, Memphis, Tenn. He can be reached at shedges@pctonline.com.
