Pest Information for Pasadena, San Gabriel Valley

As August heat bakes the historic streets of Old Town Pasadena, two pests are particularly active right now: drywood termites and roof rats. The prolonged dry spell and 85°F average temperatures push termites into swarming season—they're seeking new wood to infest, and the older Victorian and Craftsman homes with their raised foundations and poorly ventilated attics provide perfect targets. The dense tree canopy along Colorado Boulevard and near the Arroyo Seco offers roof rats ample harborage and food, while the aging infrastructure of these early 20th-century homes gives them easy entry points. The cool, humid microclimate near the Arroyo Seco also supports moisture-loving pests, but the current dry conditions are driving termites and rats indoors in search of water and cooler environments.

Homeowners in the 91101 and 91103 ZIP codes should inspect their attics for drywood termite signs like discarded wings near windowsills or piles of frass (wood-colored droppings) that look like salt and pepper. Look for mud-like tunnels on exterior walls, though drywood termites don't build mud tubes—instead, check for hollow-sounding wood when tapped. For roof rats, listen for scratching or scurrying in the attic at night, check for droppings (similar to rice grains) in the garage or crawlspace, and look for gnaw marks on wires or rafters. Also, inspect the roofline and eaves for entry points, especially where tree branches overhang—common along streets like Fair Oaks and Raymond Avenue, where mature oaks and sycamores touch rooflines. Below are the top-rated Pasadena exterminators who specialize in these specific seasonal threats.