ABSTRACTOlder conks ofGanoderma applanatumwere observed to have a whitened appearance in the context and older tramal tissues and were similar in this respect to white-rotted wood. Hyphae taken from whitened areas of the context became greatly expanded when mounted in 2% KOH and showed signs of deterioration when viewed microscopically. Holes and spore wall erosion were present in basidio-spores trapped in the current year's pore layer. Nitrogen levels and relative densities were lower in the whitened areas than in the brown current year's growth. Comparisons of relative densities between older and newer tissues of the brown rot fungusFomitopsis pinicolaindicated little difference. However, as inG. applanatum, N levels were lower in older tissues ofF. pinicola.Recycling of nutrients from older nonfunctional tissues inG. applanatumandF. pinicolaconks may be a mechanism whereby nutrients are transferred to the current year's growth. However, the whitening phenomenon and reduction of hyphal number was peculiar only to some olderG. applanatumconks. Hyphal decay (autolysis) may be a mechanism of N utilization in conks of this fungus.