Pest Control in Westbrook, Maine: What Is Getting Into Homes This October

Westbrook has two kinds of October. There is the one on the calendar, with leaves coming down along the Presumpscot and the first frost on the windshield. Then there is the one happening at the edge of your house, where every mouse, cluster fly and stink bug in the neighborhood is looking for the same thing you are: somewhere warm to spend the winter.

If you have searched for an exterminator in Westbrook this month, you are probably seeing one of four things. This guide covers each of them, what you can do yourself, and where a professional visit earns its keep.

Why Westbrook homes get so much fall pest pressure

Westbrook's building stock explains most of it. The older neighborhoods around downtown, Cumberland Mills and Frenchtown are full of houses and multi-family buildings from the mill era, with fieldstone or granite foundations, balloon framing and a century of settling. Those homes have character, and they also have gaps at the sill, around bulkheads and where additions were tied in.

The river matters too. The Presumpscot corridor, the old canal and the wooded lots toward Prides Corner give mice, voles and overwintering insects plenty of habitat a short walk from a warm wall. Newer homes off Stroudwater Street and Route 302 are tighter, but vinyl siding, attached garages and attic vents still give insects a way in.

None of this means your house has a problem. It means October is the month to look.

1. Mice moving indoors

This is the call we get most in Westbrook from late September on. House mice and white-footed mice follow warm air leaking out of a building, and a mouse can get through a gap about the width of a pencil.

Signs to check for:

• Droppings along the sill plate in the basement, under the kitchen sink, or in the drawer under the oven
• Scratching in a wall or ceiling shortly after dark
• Shredded insulation or stored fabric in the garage or attic
• Pet food or birdseed bags with a chewed corner

In multi-family buildings, which Westbrook has a lot of, mice travel along shared plumbing and heating chases. Treating one unit rarely solves it. The building has to be looked at as a whole.

Trapping takes care of the mice that are inside. Sealing the entry points is what stops the next ones. Our fall rodent exclusion guide walks through exactly where mice get in and what sealing involves, and our Westbrook rodent control page covers how we handle it locally.

2. Cluster flies in the attic and on sunny windows

If large, slow flies are gathering on a south- or west-facing window on a warm afternoon, those are almost certainly cluster flies, not house flies. They are not a sanitation problem. Cluster flies develop outdoors as parasites of earthworms, and in fall the adults collect on sun-warmed walls and work their way under siding, into soffits and up into attics to wait out the winter.

Two things are worth knowing:

• Timing is everything. An exterior treatment and sealing work done in late September and October, before the flies settle in, is far more effective than anything done in January.
• Once they are inside a wall or attic, do not spray into the void. Dead insects in a wall attract carpet beetles and other scavengers. Vacuum the ones that show up indoors and plan to seal the entry points before next fall.

3. Stink bugs, lady beetles and seed bugs

Three more insects use the same strategy, and Westbrook homeowners often see all three in the same week:

• Brown marmorated stink bugs, shield-shaped and about the size of a dime, now found in southern Maine
• Multicolored Asian lady beetles, which look like ladybugs and can gather in large numbers on light-colored siding
• Western conifer seed bugs, long, brown and slow, often mistaken for stink bugs

None of them bite, breed indoors or damage the house. They are a nuisance, and stink bugs and lady beetles both leave an odor and can stain if crushed. The fix is the same as for cluster flies: screen attic and gable vents, repair torn window screens, caulk around window and door trim, and replace worn door sweeps. A professional exterior treatment in early fall reduces how many reach the gaps in the first place.

4. Firewood pests

Plenty of Westbrook homes heat with wood or run a stove on cold nights, and the woodpile is one of the most common ways pests get a ride indoors.

• Carpenter ants nest in damp or punky logs. A few ants walking out of a log by the stove is usually just that log. Ants appearing indoors in winter with no firewood nearby is a different matter and worth an inspection, because it can mean a nest inside the structure. See our carpenter ant control page for what that involves.
• Wood-boring beetles and spiders come in on the bark and are mostly harmless indoors.
• Mice nest in the pile itself, especially one stacked against the house.

Good firewood habits:

• Stack wood off the ground and at least 20 feet from the house if your lot allows, never against the siding
• Bring in only what you will burn in a day or two
• Burn the oldest wood first
• Never spray firewood with insecticide; it does little and you will be burning it indoors
• Buy firewood locally. Maine restricts moving untreated firewood into the state to slow invasive forest pests such as emerald ash borer

A one-hour October walk-around

You can catch most of this with a flashlight and a slow lap around the house:

1. Check where the siding meets the foundation. Any gap you can fit a pencil into is a mouse door.
2. Look at the bulkhead and the garage door bottom seal for daylight.
3. Check where the gas line, oil fill, cable and AC lines enter. These are often sealed with nothing but old foam.
4. Look up at attic, gable and soffit vents for missing or torn screening.
5. Move firewood, leaf piles and stored items away from the foundation.
6. Cut back branches touching the roof.

Seal small gaps with copper mesh and exterior sealant rather than spray foam alone, since mice chew straight through foam.

When to call an exterminator in Westbrook

DIY is reasonable for a single mouse or a few flies on a window. It is time to call when:

• You are still catching mice after two weeks of trapping
• You hear activity in walls or ceilings, or find droppings in more than one area
• Cluster flies or stink bugs return to the same rooms every fall
• You see carpenter ants indoors in winter
• You manage a multi-family or commercial building where the source could be any unit

A professional visit starts with an inspection of the whole exterior and the basement or crawl space, identifies what is actually present, and ends with a written plan. Robbins Pest Services is based in downtown Portland, a few minutes from Westbrook, and provides pest control in Westbrook for homes, rentals and businesses. The inspection is free and you get a firm quote before any work starts. You can request a free inspection online or call (207) 770-0274.

If your yard backs onto woods or the river, October is also the second peak for adult deer ticks. Our fall deer tick guide explains why.

Frequently asked questions