Common Pest Problems in Franklin County, Missouri

Franklin County, Missouri covers a diverse landscape — from the suburban corridor along I-44 through Pacific and Villa Ridge, to the county seat in Union, to rural properties along the Missouri River and its tributaries in the northern part of the county. This diversity of land use and housing type creates varying pest pressures across the county, but several pest challenges are consistently reported across Franklin County as a whole.

Termites: Consistent County-Wide Pressure

Subterranean termites are present throughout Franklin County and represent a significant and ongoing risk to residential structures. Missouri falls within Zone 1 of the USDA termite probability map — the highest-risk zone — and Franklin County's climate and soil conditions are highly supportive of eastern subterranean termite colonies. Older housing stock in Union, Washington, and established rural communities in the county frequently lacks the modern physical and chemical termite barriers present in newer construction.

Annual termite inspections are recommended for all Franklin County homeowners, particularly those in homes older than 20 years or with crawlspace foundations. Finding swarmers inside in March through May is the most common first sign of an active infestation in Franklin County homes.

Brown Recluse Spiders: A Real Regional Concern

Franklin County is well within Missouri's prime brown recluse territory. D&D regularly treats homes throughout the county for brown recluse, and this pest is particularly common in homes with crawlspace foundations, older construction with abundant wall void access, and properties with storage areas that accumulate undisturbed clutter. Brown recluse is not a rare find in Franklin County — it is a common, manageable pest that responds well to professional treatment.

Mice: Fall Pressure Across the County

The agricultural landscape surrounding Franklin County's communities means fall rodent pressure is significant throughout the county. Properties adjacent to corn and soybean fields — common in the northern and eastern portions of the county — experience the harvest-time displacement that drives mouse populations into structures. Even homes in Washington and Union that appear suburban are within foraging range of adjacent rural habitat. Fall rodent exclusion and prevention are annual priorities for Franklin County homeowners.

Odorous House Ants: The Most Common Call

Odorous house ants are the most frequent pest service call across Franklin County — small, dark ants trailing in kitchens, bathrooms, and along baseboards throughout the spring and summer. The ubiquity of mulched landscaping and the county's mix of older and newer homes provides abundant outdoor nesting habitat adjacent to structures. Consistent perimeter treatment and bait-based interior management keeps odorous house ant problems under control for homeowners on recurring service.

Mosquitoes and Ticks Along the Meramec and Missouri Rivers

Properties in the river bottoms and flood-plain areas of Franklin County — along the Meramec River in the southern part of the county and along the Missouri River in the north — face elevated mosquito pressure due to periodic flooding that creates standing water and the dense riparian vegetation that supports adult mosquito resting populations. Tick pressure is similarly elevated in the wooded river bottom properties. Yard treatment programs are particularly valuable for Franklin County properties with any proximity to these waterway corridors.