Rat Control (Norway Rats)

Norway rats leave evidence a homeowner can verify without a flashlight lecture. Droppings are blunt-ended and roughly three-quarters of an inch — noticeably bigger than the rice-grain pellets a mouse leaves. Burrow openings are two to four inches across, usually within a few feet of a foundation wall, a shed skirt, an alley trash pad, or the soft dirt behind a Formstone-fronted row home. Along interior joists and basement walls you will see dark rub marks where oily fur has polished the wood. A Norway rat only needs a gap about a half-inch wide to squeeze through, which is why loose basement door sweeps, unscreened crawl vents, and the annular gap around a water service line all count as doors.

Baltimore's rear alley grid is what makes this a different job than suburban rodent work. Row homes in Canton, Highlandtown and Fells Point share party walls and a common alley where trash sits, so a colony feeding on one block's cans travels under three or four properties. Treating only your side of the wall moves the problem sideways. That is the reason the inspection walks the alley pad and the neighboring grade line, not just your basement, and it is the reason many residents also file a 311 report so the city's abatement crews are working the public right-of-way while private treatment handles the property itself. Older sections of the city carry a second route most homeowners never consider: clay sewer laterals. Norway rats swim, and a cracked lateral or an open floor-drain trap in a Bolton Hill or Mount Vernon basement can deliver rats from the sewer straight into a finished room with no exterior entry at all.

Choose rat-specific service over general mouse control when the droppings are large, the gnaw damage is coarse, you hear heavy movement rather than light scratching, or you can find a burrow hole outside. Mouse programs lean on dozens of small interior placements; Norway rat programs live or die on exterior burrow work and physical exclusion. The honest trade-off is timeline and cost: a rat job is rarely one visit, and sealing gaps with hardware cloth, mortar and steel is labor you cannot skip if you want the result to hold past the first cold snap. Homes backing onto green space — Patterson Park, Druid Hill Park, the Gwynns Falls/Leakin Park edge — see steadier outside pressure, so those properties usually need a maintained exterior perimeter rather than a one-time cleanout.

Safety questions get answered before anything is placed. Exterior rodenticide, when it is used at all, goes into locked tamper-resistant stations anchored where a dog, a toddler, or a backyard chicken cannot reach the bait. Inside occupied living space, trapping is the default. Gardens, raised beds and pet runs get flagged during the walkthrough so placements stay away from them. Note that Baltimore City is an independent city, not part of Baltimore County, so alley ownership, trash-pad rules and abatement contacts differ from a Towson or Dundalk address — the inspection accounts for which jurisdiction the property sits in. Find the source, seal the home: that order matters, and reversing it is why store-bought traps and bombs keep failing on these blocks.