German cockroaches favor warm, humid spaces near food and water — kitchens, behind appliances, under sinks — and Duvall's a temperate marine climate with heavy fall-through-spring rainfall and comfortable, mild summers keeps them active most of the year. American cockroaches, larger and reddish-brown, prefer basements, drains, and utility rooms. A mix of older wood-frame homes and newer suburban construction, many without air conditioning given the historically mild summers, and prone to moisture issues given the rain.
Treatment starts with locating the harborage points — the tight, warm, food-adjacent spaces roaches actually live in — and applying gel bait directly there rather than spraying open floor space. This targets the colony at its source and avoids the resistance issues that plague over-the-counter sprays. We follow up to verify the population has collapsed, not just scattered.