Ants are incredibly common insects that live in colonies and can be found almost anywhere. Two of the most prevalent ants are carpenter ants and black ants, which look very similar to the naked eye. However, there are some key differences between carpenter ants and black ants that allow you to distinguish between them.
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Size and Appearance
The most noticeable difference between carpenter ants and black ants is their size. Carpenter ants are much larger, ranging from 1/4 inch to 3/4 inch in length for a worker ant. Black ants are smaller, with workers only reaching 1/8 to 1/4 inch in length.
In general, carpenter ants have a more robust, reddish-black coloration to their bodies while black ants can appear dark brown or black. Carpenter ants also have a more evenly rounded thorax compared to black ants, which have a thorax that angles up towards the abdomen.
When it comes to the antennae, carpenter ants have antennae with elbowed angles while black ants have straight antennae. Carpenter ants also have larger mandibles than black ants.
Nests
Carpenter ants and black ants create nests in very different areas. As their name implies, carpenter ants burrow into wood to make their nests. They excavate galleries and tunnels in dead trees, logs, wooden constructions or timber-frame structures.
Black ants, on the other hand, do not tunnel into wood. They make nests in soil, retaining walls, under stones or in existing cavities and crevices. The entrances to their underground nests are often found at the base of trees, rocks or walls.
Behavior and Habits
The behavior and habits of carpenter ants and black ants provide more clues to tell them apart:
- Carpenter ants are mainly nocturnal and forage for food at night.
- Black ants forage day and night.
- Carpenter ants feed on sources of protein and sugar while black ants prefer sweets like honeydew from aphids or sugar water.
- Carpenter ants walk in a straight line along the edges of structures. Black ants take more winding, irregular paths.
- Carpenter ants tunnel into wood to create galleries while black ants only nest in existing cavities.
- Black ants are quicker moving and erratic when foraging while carpenter ants move at a steadier pace.
Observing their activity patterns, food sources and walking paths can help indicate if you are dealing with carpenter ants or black ants around your home.
Identifying the Species
There are different species of carpenter ants and black ants, which can make an identification more complicated. Some key species include:
Carpenter Ant Species
- Black carpenter ant (Camponotus pennsylvanicus) – Large and black throughout the US
- Western carpenter ant (Camponotus modoc) – Mainly on the west coast
- Florida carpenter ant (Camponotus floridanus) – In southeastern states
- Red carpenter ant (Camponotus ferrugineus) – Reddish ants in New England
Black Ant Species
- Black pavement ant (Tetramorium caespitum) – Small black ants with peaked thoraxes
- Pharaoh ant (Monomorium pharaonis) – Tiny light brown or yellow ants
- Little black ant (Monomorium minimum) – Very small, slow moving black ants
- Crazy ant (Paratrechina longicornis) – Very long legs and antennae
There are many overlapping traits even at the species level, so identification often requires inspecting worker ants under a microscope. Looking at the antennal segments, thorax shape, color patterns and other morphological features is needed for a definitive ID.
Winged Ants
Another time when identifying carpenter ants vs black ants can be tricky is when they both have winged reproductive ants emerging in the springtime. However, there are still some differences:
- Carpenter ant reproductives have darker, blackish wings while black ant wings are lighter in color.
- Carpenter ant reproductives are much larger with bodies 0.5 inch (12 mm) or more.
- Black ant reproductives range from 0.1875 to 0.25 inch (5-7 mm) long.
- The wings of black ants are shorter than their bodies while carpenter ant wings are about the same length as their bodies.
Signs of an Infestation
Telltale signs around your home can also indicate if you are dealing with a carpenter ant or black ant problem:
Carpenter Ant Infestation Signs
- Holes and nicks in wood surfaces
- Hollow sounds when tapping on wood
- Coarse sawdust around or under wood
- Trails of large, black ants along edges and wood grain
- Noisy activity in walls and ceilings as ants tunnel
Black Ant Infestation Signs
- Long trails of small, black ants along walls or baseboards
- Black ants crawling under doors, window sills, around pipes
- Nest mounds around building foundations
- Quickly moving and erratic black ants in kitchens or bathrooms
Paying attention to these signs can confirm which species has invaded your home before turning to control methods.
Control and Prevention
Once you have correctly identified carpenter ants or black ants, you can move forward with targeted control methods including:
Carpenter Ant Treatment
- Following trails to locate and directly spray nests
- Applying boric acid powder into galleries
- Using foam insecticides into wall voids and wood galleries
- Filling outdoor rotting wood and tree stumps with insecticidal dust
- Treating ant trails with liquid ant bait
Black Ant Treatment
- Applying granular baits around nests and foraging trails
- Using liquid or gel baits for sweet-loving species
- Sealing indoor entry points like small cracks
- Removing debris piles and rotting wood outside
- Spraying insecticide barriers around nests
Sanitation and moisture control will also discourage future ant colonies of either species. Targeting the specific species with appropriate methods prevents wasted time and ineffective treatments.
Key Differences Summary
Here is a quick summary of the main differences between carpenter ants vs black ants:
| Difference | Carpenter Ant | Black Ant |
|---|---|---|
| Size | 1/4 – 3/4 inches long | 1/8 – 1/4 inches long |
| Color | Reddish-black | Dark brown to black |
| Antennae | Elbowed angles | Straight |
| Nest Location | Tunnels in wood | Soil, retaining walls, etc. |
| Foraging Time | Nocturnal | Day and night |
| Food Sources | Protein and sugars | Sweets like honeydew |
| Movements | Steady, straight lines | Quick and erratic |
Being able to recognize these differences will allow you to quickly identify carpenter ants and black ants. This knowledge lets you use appropriate control methods to get rid of an infestation.
Conclusion
Carpenter ants and black ants may look very similar at first glance, but observing their size, color, nesting habits, food preferences and movements reveals distinct differences between the two. Carpenter ants are much larger and tunnel into wood while black ants are smaller and nest in cavities. Understanding the nuances allows pest management professionals and homeowners to correctly identify carpenter ant vs black ant infestations before treating them.