Pest Control in Saint Paul, MN

Why do stone and brick foundations let mice and rats in?

A foundation laid in stone or brick has mortar joints, and mortar weathers over a century of freeze and thaw. Gaps open at the sill where the wood frame meets the masonry, around old coal-chute doors, and where later owners ran gas, cable and plumbing through the wall. A mouse needs only a gap of about a quarter inch, and rats, while larger, will widen an opening that is already loose.

These entries matter most in autumn, as the nights cool and animals look for warmth. Rat control on an older Saint Paul property usually starts outside, with a look at burrows along the foundation, the bluff-side edge of the lot and any alley or fence line, and then moves to the basement. Mice follow the same entry points; our mouse control page covers that route.

Sealing is slow work on irregular masonry, because stone does not sit square. A technician may recommend mesh and mortar patching rather than a tube of caulk. It is worth asking what material is planned and where, since chewable fillers fail.

What lives in the ravines, bluffs and parks, and how does it reach an attic?

Squirrels, raccoons and bats use the trees and rocky ground along the bluffs, and an older house with a loose soffit, a failing chimney cap or a gap under the ridge is easy to enter. Mature trees often overhang roofs on streets near Como Park and Highland Park, which gives climbers a route straight to the shingles.

Winter and late winter are common times for squirrel and raccoon trouble, since animals look for a dry, warm place to den. Bats are a spring-to-summer question. We do not give legal exclusion dates here, because the rules can change and should be confirmed before any work; a technician can explain what applies when you call. See squirrel and raccoon exclusion and bat exclusion.

Never go into an attic to chase an animal yourself. A cornered raccoon can bite and scratch, and a mother with young will defend a nest.

Boxelder bugs on Summit Avenue and apartments on Grand

The same sunny walls that make Summit Avenue photogenic collect insects in October. University of Minnesota Extension notes that boxelder bugs favor buildings with southern exposure and that Asian lady beetles overwinter on the sunny sides of tall buildings; a three-story Victorian with a south porch is an ideal wall. See boxelder bug and Asian lady beetle control.

In the brick apartment buildings around Cathedral Hill and Grand Avenue, shared walls and heated corridors are the bigger issue. Cockroaches and mice move between units, and the best results come from treating the whole building together. Cockroach control in a walk-up has to include neighbors, not just one door.

What does the winter do to a bluff-side lot?

Saint Paul has a real dormant season, and the pests that stay busy are the ones indoors. Once the ground freezes, burrowing animals lose their outdoor options and press toward basements, sewer connections and foundation gaps. Meanwhile insects that moved in during October sit quietly in walls and attics, and a mild afternoon in January can bring a few out onto a window.

Snow cover brings its own detail. Voles feed on lawns under good snow, and the damage shows when the snow melts, which on a steep bluff lot can reveal runways and chewed shrub bark all at once. Lawn grass usually recovers slowly; woody plants can be killed. Our guide to voles under the snow shows which damage to wait on and which to treat as permanent.