 The Amylostereaceae are white rot pathogens . They disintegrate the lignin of the host wood , whereby the infested wood parts become less stable and take a fibrous structure . The wood bleaches as fungal enzymes break down and remove the brown @-@ pigmented lignin . The distribution in wood takes place mainly along the transport channels in the xylem . If the wood is crosscut , the red rot is vertically positioned , on which bleached , infested areas contrast with intact wood . Symptoms of infestion by the symbiotic partner — wood wasps — include circular exit holes in the crust and acute stress through dryness , common in hanging , falling or tanning needles . 
