The colonies can be located by placing something sweet out and watching the ants take it back to their nests. The workers may forage up to 300 feet from their nest or satellite nest. If the carpenter ants are not seen in the winter the nest may be outside in a stump, fire wood, old trees, fence posts or other areas of damaged wood. Although some carpenter ants are active during the day, the majority will be active after dark with peak time between 10pm and 2am.
Many field ants are very similar in size and color to carpenter ants and may be misidentified. The main distinguishing characteristic of carpenter ants is the smooth thorax (back) the field ant=s back is not evenly rounded. Field ants are commonly found outside with the nest in the soil.
Little Black Ants
Size: Workers:
1/16″ (1.5-2 mm)
Queens:
1/8″ (3-4 mm)
Color:
Dark brown to black
Antenna: 12-segmented with 3-segment club
Thorax:
Lacks spines; unevenly rounded
Pedicel:
2-segmented
Biology:
The colonies are of moderate to large in size and have many queens. Winged reproductives are seen from June to August. Nests can be found within a structure in decaying wood, between wood and masonry, and in wall voids. Outside nests are under rocks, in logs, or in the lawn. They feed on other insects, sweets, honeydew, grease, oil, meats, meal, and fruits. They forage in trails that can easily be seen on foundation walls and along walkways.
Odorous House Ants
Size:
Workers 1/16-1/8″ (2.4-3.25 mm)
Color:
Brown to black
Antenna:
12-segmented, without a club
Thorax:
Lacks spines; unevenly rounded
Pedicel:
1-segmented with node hidden by base of abdomen
Biology:
The colonies range from several hundred to 10,000 ants and have many queens. Developmental time (egg to adult) is 34-83 days in summer and 6-7 months in the winter. Swarmers are seen from May to mid-July. The workers and queens live several years. Nests can be found within a structure in wall voids around hot water pipes and heaters, around sinks, behind insulation in crawlspaces and in attics. Outside nests are found along the foundation, under mulch along concrete joints, under stones, under logs, and even with other larger ants. These ants feed on sweets, protein, plant secretions, and honeydew from other insects. When disturbed, these ants will raise their abdomen similar to acrobat ants, however odorous house ants cannot cover their body or head with their abdomen.
Pavement Ants
Size: Workers:
1/16-1/8″ (2.5-4 mm)
Queens:
3/8″ (8 mm)
Color:
Light brown to black with paler legs and antenna
Antenna:
12-segmented with 3-segmented club
Thorax:
Pair of small spines, unevenly rounded
Pedicel:
2-segments