Why Pests Get Worse After Rain in Alabama

Rain can change moisture and shelter conditions around a house, making pest activity more noticeable. Identify the insect and inspect drainage, door gaps and damp storage areas before assuming that every sighting needs another application.

Why does rain change pest activity?

Argentine and odorous house ants nest shallow, under mulch and stones and along the foundation. When those nests flood, the colony moves the brood to higher, drier ground — and the highest, driest ground on the lot is inside your walls. This is the ant trail that appears the day after a storm and seems to come from nowhere. Fire ants do the same thing in the yard: a saturated colony pushes up above the water line, and the mounds that "appeared overnight" were there all summer, underground.

Reference: Repair leaks and avoid water accumulation around the home. EPA: Pest prevention and pesticide use.

Roaches: out of the drains

American cockroaches live in storm drains, sewer lines, and crawlspaces. A flooded drain system pushes them up and out, into bathrooms through floor drains and into crawlspaces that are now wet. Smokybrowns get flushed out of gutters and tree holes. Both end up looking for a dry, warm place, and the garage and the bathroom are it.

Millipedes, centipedes, and springtails: the surface army

Saturated soil drives millipedes, centipedes, earwigs, and springtails to the surface by the thousand, and they migrate across pavement toward any wall. They are harmless, they die indoors within a day or two, and they are almost impossible to prevent entirely in the week after a flood. What reduces them is the same thing every time: a dry band along the foundation, no mulch against the slab, no leaf litter piled by the door, and a treated perimeter.

Mosquitoes: the seven-day clock

This is the one that arrives late. Every container, gutter, tarp, wheelbarrow, and low spot that filled during the storm is a mosquito nursery, and in summer heat the cycle from egg to biting adult runs about a week. The storm was Saturday; the mosquito cloud is the following weekend. Dumping standing water within a couple of days of a big rain is the single most effective mosquito step there is. The seasonal program treats the resting sites; it cannot empty your flowerpot saucers.

Termites: the quiet one

Rain does not create termites, but it creates the conditions. Wet soil against a foundation, a gutter overflowing onto the sill, a crawlspace that stays damp for a month — that is the moisture subterranean termites need to reach the wood. A season with a lot of storms is a season to look at the crawlspace and the downspouts. What to look for is in termite damage signs.

Spiders, mice and rats, and wasps after heavy rain

The common pests after a storm are not only the ones that live in the soil. Spiders follow the insects they eat, so a wave of crickets and millipedes along the foundation is often followed by more spider activity in the garage and around door frames. Mice and rats look for dry shelter when burrows, woodpiles and drainage ditches flood; a rodent that finds a gap under a garage door or around a pipe may move into wall voids and stay. Paper wasps and other wasps rebuild under eaves and in sheds once the weather clears.

How to keep pests out of your home after a storm

Most pest problems in Alabama homes after rain come back to two things: moisture and entry points. A humid, damp foundation draws insects toward the house; a gap lets them in.

• Seal gaps around pipes, cables and vents, and replace worn door sweeps on exterior and garage doors.
• Trim shrubs and limbs so they do not touch the siding or roof.
• Keep mulch beds thin and pulled a few inches back from the slab.
• Store pet food and birdseed in sealed containers, indoors and out.
• Check the crawl space after heavy rain and fix leaks before the wood stays wet.

Should you spray after it rains?

Usually not right away. A DIY spray on wet ground and on an ant trail tends to scatter the pest rather than solve it. Identify what you are seeing first; a fire ant mound in the yard, roaches in a floor drain and a swarm of winged termites are three different problems with three different treatments. Winged insects indoors in spring are worth a closer look, because they may be termite swarmers rather than flying ants.

A year-round local pest control plan keeps a treated barrier along the perimeter and brings an inspection on every visit, so the conditions behind storm-driven pest pressure get looked at on a schedule instead of only after an infestation. Our customers in Birmingham, Shelby County, Lake Martin and Huntsville are on the same bi-monthly schedule.

Frequently asked questions

What bugs come out after rain in Alabama? Ants, cockroaches, millipedes, centipedes, springtails, earwigs, crickets and spiders are the most common, followed about a week later by mosquitoes breeding in standing water.

Will the bugs go away when it dries? Many surface insects die off or move back outdoors within days. Ants that moved a colony indoors, roaches in drains and rodents usually do not leave on their own.

When should I call a professional? Call when activity continues after the ground dries, when you see winged insects or mud tubes, or when rodents are in the house.

The week-after checklist

• Dump every container of standing water on the lot within 48 hours.
• Clear the gutters and make sure downspouts carry water away from the foundation, not against it.
• Pull wet mulch and leaf litter back from the slab and the doors.
• Run water in floor drains and unused sinks to refill the traps that keep roaches out.
• Do not spray the ant trail — it fragments the colony. Bait it, or call.
• Check the crawlspace for standing water and get it dried.

If you are on the bi-monthly plan and the storm brought something in, that is what free re-service between visits is for. One call, and we come back out.

Call the office nearest you — Birmingham (205) 991-2882, Alabaster (205) 940-6360, Lake Martin / Alex City (256) 234-6162, or Huntsville (256) 937-7676 — or request a free quote and we will take it from there.

No One Cares Like EnviroCare.