Michael Christie, Greenwood: ” Even when a tree is at its most vital, only ten percent of its tissue—the outermost rings, its sapwood—can be called alive. All the rings of inner heartwood are essentially dead, just lignin-reinforced cellulose built up year after year, stacked layer upon layer, through droughts and storms, diseases and stresses, everything that the tree has lived through preserved and recorded within its own body. Every tree is held up by it own history, the very bones of its ancestors.” (484)
Arborilegium 