Wet spring could bring more ants — here's how to fight them

The Chicago suburbs have seen plenty of precipitation this spring, and that's a good thing for lawns and gardens. But it could also mean trouble with ants.

Ant colonies are known to flee into houses when the ground gets wet. Suburban pest control companies are noticing an uptick in ant-related calls.

“We're getting dozens of calls a day,” said Rebecca Fyffe, the director of research at Landmark Pest Management, which has offices in Arlington Heights and Schaumburg. “When it's rainy and wet in the spring and lush, we get tons of ant calls.”

Friends and do-it-yourself websites have probably offered a litany of remedies — dryer sheets, baby powder mixtures and ant baits.

Fyffe said scientific research has shown bait gels and granular products ants carry back to their colonies, which in turn destroys the problem at its source, are the best ways to eliminate ants. Sprays spread pesticides in the house and may not solve the problem.

What works and what doesn't may depend on the type of ant that has moved in to your house.

Carpenter ants

These dull black ants, which can grow up to three-fourths of an inch, dig into damp wood, often near leaking pipes or inadequately sealed windows. They don't eat wood but rather forage human food and insects. The ants burrow into door frames, wall voids and foam insulation, according to the Illinois Department of Public Health, and that can require professional help. “It's important to deal with them swiftly and completely,” Fyffe said.

Pavement and odorous ants

These two species, especially, move inside during rains. The pavement ant is dark brown and about one-sixth of an inch long. The odorous ant releases an ammonia-type scent when crushed. Both are the easiest type of ant to eliminate by properly sealing windows and cracks in a house's foundation with caulk, Fyffe said.

Pharoah and ghost ants

Though neither are native to Illinois, these species still make it into houses, many times through indoor plants bought at garden centers. Pharoah ants are yellowish brown and one of the few types that can sting, while ghost ants are defined by a dark head and translucent legs and body. Fyffe suggested seeking a professional to help rid houses of an infestation of these species.