Spruce bark beetle activity was monitored over 14 years on a transect through a mixed white spruce stand on the Kenai Peninsula, Alaska. Data confirmed bark beetle preference for attacking large-diameter, slow-growing spruce. Increased bark beetle activity was noted on north facing slopes; the least activity was on ridge tops. Moisture stress brought about by low soil temperatures is believed to be the cause for increased susceptibility of white spruce to beetle attack on north facing slopes. A rudimentary guide is given to rate uninfested spruce timber for probable high or low losses if attacked by spruce beetles.