nice overview with examples http://forestpathology.cfans.umn.edu/archaeologicalwood.htm http://forestpathology.cfans.umn.edu/archaeologicalwood.htm http://forestpathology.cfans.umn.edu/archaeologicalwood.htm Decay in ancient and historic woods nice overview with examples http://forestpathology.cfans.umn.edu/archaeologicalwood.htm