Yes, most wooden park benches are specifically treated to resist rot and insects. This is essential for their longevity in outdoor environments. The most common and effective method is pressure treatment. In this industrial process, the lumber is placed in a pressurized tank, forcing preservative chemicals deep into the wood fibers. These chemicals, such as ACQ (Alkaline Copper Quaternary) or micronized copper, are toxic to fungi, termites, and other wood-boring insects, providing long-term protection from within.
Beyond industrial treatment, many benches receive a secondary layer of defense. This often involves water-repellent sealants or stains applied to the surface. These coatings create a barrier against moisture—the primary cause of wood rot—and can also contain UV inhibitors to prevent sun damage and fading. The type of wood also matters. While pressure-treated Southern Yellow Pine is a standard, naturally durable woods like cedar, redwood, or tropical hardwoods (e.g., Ipe) are sometimes used for their inherent resistance.
Regular maintenance is the final key. Even treated wood benefits from periodic cleaning and reapplication of sealant every few years to maintain its protective shield. So, when you see a wooden bench in a park, it's likely gone through a robust treatment process to ensure it remains a sturdy and welcoming place to sit for years, defying the elements and pests.