Affected trees show marked reduction in height and diameter growth.
The crown thins and yellows, and may frequently produce a distress crop of cones. Early in the decay process, crescent-shaped or semicircular reddish brown staining of the wood may be observed. As decay progresses, the wood softens. The earlywood disintegrates more quickly than the latewood in each annual ring, resulting in a laminated ring rot where the annual rings of the wood separate. Small oval pits appear on both sides of the separated wood sheets.