Thatching ants, Pharaoh ants, Thief ants, Little Black ants, Velvety Tree ants, Ghost ants, Argentine ants, Larger Yellow ants, Corn Field ants.
Thatching ants are large ants, about the size of your average carpenter ant. The most common species is usually red and black, although there are species that are all black or all brown.
They are called thatching ants because their nests are made out of thatch - especially grass, weed, and tree twig stems. They can pull these materials into a wall void, or attic, and will bring it into a sub area, especially on top of insulation.
In the wild, these ants will nest in rotten logs, or they will make big mounds of thatch. The nest usually extends down into the ground - at least as far as the mound is high.
If these ants are nesting away from your home, somewhere on your property, and they are not invading your home, please consider leaving them alone. They are a very beneficial ant, that helps to control other pests. They are the ultimate 'green' pest control.
If the are living in your home, or venturing inside, you should get rid of them, as they do bite and they spray formic acid in the bites, which can really sting.
You can tell them from carpenter ants, by the fact that they are all the exact same size, and their bodies are shaped differently.
Pharaoh ants are a tiny (less than 1/8th inch long) yellow, dark yellow, or light brown ant. They act much like Odorous House ants but are somewhat harder to get rid of. The treatment is similar, but with more reliance on protein based baits.
They are huge pest in hospitals, where they are known to feed on wounds. They are hard to control in multi-unit housing as unit occupants who spray over the counter pesticides, fragment and scatter the ants all over, making it much harder to eliminate them.
Thief ants are about the same size as Pharaoh ants and range from brownish to yellowish and may have a red tinge
Treatment for Thief ants is the same for Pharaoh ants and the Odorous House ant treatment program should be followed. Protein baits should be used with carbohydrate based baits.
These ants should be treated like Odorous house ants as they are similar in size and foraging habits.
Velvety Tree ant workers will vary from 1/8 to 1/4 inch, with brownish to black head, a red thorax, distinctive velvety black abdomen, and very distinct odor when crushed.
These ants are known to damage wood like carpenter ants do, but they can often be distinguished from carpenter ants, both both their physical characteristics and the fact that often trail along the tops of walls.
Ghost ants are about the same size as Pharaoh ants and have similar habits.
The Odorous House ants treatment strategy works well on this ant that loves sweets, especially aphid secretions, fermenting fruit, and plant nectar.
Argentine ants are about the same size as the larger of the Odorous house ants (1/8th inch) and are typically a dull brown. Baits can be tried with this ant and they sometimes help - but are often ignored. All natural ant dusts in cracks and crevices, and super low toxicity ant control materials sprayed outside and sometimes inside work bests. Be careful not to use pyrethroids or other repellents.
These two species are collectively referred to as moisture ants - see the link to the left
Since almost all ants are little in comparison to us, lets set some size parameters that should be easy for all of us.
If you stack pennies on top of each other you will get 16 to 17 pennies in an inch high stack. All the ants noted below are sized by the thickness of a penny. So the thickness of a penny is about a sixteenth of an inch wide.
Tiny: Ants as small as 1 to 2 pennies are thick:
Big Headed ants, Thief ants, Pharaoh ants, Rover ants, some species of Odorous house ants, Ghost ants, Large yellow ants, and Little Black ants. (Yes, there is a little black ant species named: Little Black ants. All of these ants are about a 1/16th of an inch long.
Little: From 2 to 3 pennies thick:
Acrobat ant, Argentine ant, Cornfield ant, Pavement ants, White Footed ant, and some species of Odorous House ants. These ants are about an 1/8th of an inch to just over an 1/8th.
Medium: From 3 to 4 pennies thick:
Velvety Tree ants, Carpenter ants start at this size, at least some species, and even the minor workers of the larger species. Up to a quarter of an inch long.
Carpenter ants may be from 4 pennies to 9 pennies wide. If you are seeing ants that range in size but all look the same, same color and shape- you probably have Carpenter ants. If they are all exactly the same size, you may have some species of Thatching ants.
Ant color is based on the same factors that govern hair color in humans. If you have more pigment the color will appear darker. How many shades of brown hair do humans have? Combine that with the fact that there are almost always more than one species of each type of ant - like with flowers. The color of an ant is the least reliable method of identifying it.