Carpenter ants are large reddish-brown insects about 1/4 to 1/2 inch long.  They usually nest outdoors in stumps and logs where the wood contacts the soil and moisture is plentiful, but sometimes enter homes in search of food, water or nesting sites.  Carpenter ants prefer to nest in wood that has been damaged by termites or decay.  These ants do not eat wood (as is the case with termites) but excavate in it to rear their young.  They feed on honeydew, insects and household food scraps.   This species is active at night and forage for food up to 300 feet from the nest. They enter the structure around door and window frames , eaves, utility lines and branches that touch the building.
Crazy ants are black and 3 mm long, with long legs, and workers move erratically.  Colonies are usually found in both moist and dry environments.  Outdoors, nests are often in wood, tree holes and in mulch.  Indoors, nests are often in wall voids and under stored items.   Their preferred foods are insects and sweets, but they will feed on almost any household food.
Ghost ants are 1 mm long, with a black head and thorax and clear abdomen and legs.  They usually nest outdoors and forage indoors, however, potted plants are a favorite nesting site indoors.  This ant has a musty odor when squashed.  It has a high need for moisture and is often seen in kitchens and bathrooms.The workers run rapidly and erratically and feed on sweets and protein.
Pharoah ants are rust-colored and 2 mm long.  They usually nest indoors (in wall voids, refrigerator insulation, books, etc.).  Pharaoh ant colonies tend to be large with workers numbering in the thousands to several hundred-thousand.These ants nest in warm, humid areas near sources of food and water.  They commonly use electrical and telephone wires as a highway system to travel through walls and between floors.
Fire ants are reddish-brown and 3 to 6 mm long.  Fire ants build large mounds in open, sunny areas and can forage indoors.  Typical mounds are rounded, being up to 18″ high and 24″ in diameter, each with several tunnels just under the soil surface extending out several feet.  Fire ant stings can be numerous and very painful.  Their sting commonly causes a white pustule to develop and takes many days to heal, often leaving a slight scar.