German cockroaches favor warm, humid spaces near food and water — kitchens, behind appliances, under sinks — and Mount Lemmon's a mountain climate with real winter snowfall, cool summers, and none of the extreme heat that defines most of Arizona keeps them active most of the year. American cockroaches, larger and reddish-brown, prefer basements, drains, and utility rooms. Wood-frame homes and log-style cabins built for cold winters, many on forested or high-desert lots at 5,000-7,000+ feet elevation.
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.