Subterranean termites form colonies and forage for wood in soil, which provides moisture and protection from extreme temperatures. As a result, subterranean termites are more widespread than drywood termites, which are more vulnerable to extreme cold. Also unlike drywood termites, subterranean termites don’t live in the wood they’re eating. Since their colony size is not limited by wood, one subterranean termite colony can cause more structural damage than one drywood termite colony. Although subterranean termites occur in every state except Alaska, structural infestations are more common in warmer climates. Subterranean termites are limited by frozen topsoil in areas where winters are extremely cold, reducing the overall number of structural infestations in these areas.