Little piles of sand along sidewalk cracks and driveway joints are one of the first signs of pavement ants in Nampa. These small, dark ants nest under concrete, pavers and slabs, and in warm weather they forage across patios and into kitchens through cracks in the foundation. In spring, you may also see them swarming on the driveway as neighboring colonies fight over territory.
Here’s how to identify pavement ants, why they do so well in Nampa and what you can do to keep them outside.
What Are Pavement Ants?
- Size and color. About one-eighth of an inch long, dark brown to black, with light-colored legs.
- Distinctive features. Fine parallel grooves on the head and thorax, and two small spines on the back. You’ll need a magnifying glass to see them.
- Nesting. Under sidewalks, driveways, patio slabs, pavers and foundations, and sometimes in walls and under floors near the slab.
- Diet. Almost anything: sweets, grease, meat, seeds, pet food and dead insects.
Our ant identification guide shows how pavement ants compare with odorous house ants and carpenter ants.
Why Pavement Ants Thrive in Nampa
Concrete soaks up heat during the day and holds it into the night, giving colonies under slabs a warm, sheltered home. Irrigated lawns next to sidewalks and driveways keep the soil underneath moist enough for digging, and newer subdivisions have plenty of slabs, patios and pavers. Colonies stay active from spring into fall and can forage inside heated homes even in winter.
Signs of Pavement Ants
- Small mounds of sand or soil in pavement cracks, along driveway edges and between pavers
- Trails of ants along foundation edges, baseboards and kitchen counters
- Swarms of ants fighting on sidewalks or driveways in spring
- Winged ants indoors in late spring or summer, often near the slab or a basement
What You Can Do
Remove food sources
- Keep pet food indoors or pick it up between meals.
- Clean outdoor grills, patio tables and play areas after use.
- Keep trash and recycling bins closed, and rinse containers before tossing them.
- Indoors, wipe counters and sweep floors, and store food in sealed containers.
Seal cracks and gaps
Fill cracks in sidewalks, driveways and patios with concrete crack filler or polymeric sand between pavers. Caulk gaps where the slab meets the siding, and around pipes, wires and door frames. This won’t remove colonies already under the concrete, but it cuts off the easy routes inside.
Adjust the landscaping
- Leave a strip of a foot or so along the foundation free of mulch and plants.
- Keep irrigation from soaking the soil right next to the slab.
- Trim plants that touch the house, and move firewood and stored items away from the walls.
Use gel bait carefully
Ant gel bait placed along active trails lets workers carry food back to the colony. Follow the label for placement and storage, and don’t spray insecticide near bait, since that keeps ants away from it.
Penn State Extension’s guide to pavement ants has more on their biology and habits.
When to Call a Professional
Call for help if ants keep coming back inside, if you see them in multiple rooms or if winged ants are emerging indoors. A technician can track trails back to nests under slabs, treat the perimeter and entry points, and use baits inside where needed. Our guide to ant and insect control that lasts explains how ongoing service keeps colonies from rebuilding. If you also have odorous house ants in the kitchen, see our post on stopping odorous ants.
Ants are part of our residential pest control, along with spiders, wasps and hornets, mice, rats and fall invaders. We offer quarterly, bi-annual and one-time service. Quarterly service plan customers get free return visits. No contracts; cancel with 30 days’ notice. We also treat parking areas, walkways and buildings at commercial properties.
Pavement Ants Through the Year
Pavement ants follow the seasons. In spring, colonies wake up and you’ll see the first piles of soil along sidewalks and driveways. Early summer brings swarms of winged ants, which are reproductive ants leaving to start new colonies, often after a warm rain. Through summer, foraging trails get longer and more visible. In fall, activity tapers off outdoors, but ants nesting under a heated slab or near a furnace can stay active indoors well into winter.
Pavement Ant FAQs
Are pavement ants harmful?
They’re mostly a nuisance. They can bite or sting, but it’s minor. The bigger concern is ants in the kitchen and food left out, plus soil piled along walkways and slab edges.
Why are there winged ants in my house?
Winged pavement ants are common in early summer. They’re reproductive ants leaving the colony to mate and start new ones. Seeing them indoors can mean a colony is nesting under the slab or in a wall, so it’s worth watching where they come from. Ants have a pinched waist and elbowed antennae, which helps tell them apart from other winged insects.
Do pavement ants damage concrete?
No. They move soil out from under and around slabs and through existing cracks, but they don’t break down concrete.
Pavement Ants Around Your Nampa Home?
ProGuard is based in Eagle and serves homes and businesses in Nampa, Boise, Meridian, Caldwell, Star, Middleton, Emmett and Garden City. Call (208) 352-2062 or contact us to schedule an inspection and an ant control plan.