Infestation
Nests built in wet or moisture-damage wood; in trees and stumps, wood piles, and structural wood wet by rain water, or leaking down spout or roof. Winged queens common in spring; indoor nests are active in February and March.
Identification
Large black or reddish brown ants; weak trail-making, workers from outdoor nests will forage inside; nests may have small amount of fibrous frass nearby; workers forage at night in late summer.
Control
Remove damaged wood, fix leak causing problem; treat wood and nest with liquid pyrethroid; use granular bait where foraging workers are seen.
