Dictionary MAIN PAGE Text & Grap

Tree Decay - Tree decay is a process that starts after wounding and involves the tree, pathogens, and environment, as highly ordered wood becomes disordered. The tree is an organism that exerts a survival pressure after wounding. Decay is a process where order goes to disorder. Energy is required to maintain order. Energy comes from the sun. The energy for defense comes from stored reserves in living cells. Tree defense is a dynamic process. Tree decay is also a dynamic process. Tree decay has been confused with wood decomposition. Decay was studied in the laboratory using heartwood. Heartwood was considered a dead, non-reactive tissue in trees. If it was dead in trees, it could not change to a different degree of "deadness" in the laboratory. And, the heartrot concept defined heartrot as decay of the heartwood. So, heartwood in the tree and heartwood in the laboratory were considered the same. No provisions were made for discolored heartwood, or wood that was not heartwood, but the color of the wood was such that the wood was called heartwood. The results from the laboratory were extrapolated to the tree. This was the moment of "original sin" in tree biology. True, at the molecular level, the decay process in dead wood in the laboratory is the same as dead wood in a tree. However, in a tree, wood does not pass from living to dead in one short moment. A long series of interactions between tree and microorganisms takes place. This part of the story was completely lacking from the view given by the heartrot concept. Early workers gave an excellent and accurate description of wood decomposition, but they did not give a description of tree decay. The tree and all the dynamic processes were lacking from the heartrot, wood decomposition view. Add to this the belief that only wood-inhabiting decay-causing fungi were involved in the process, and the confusion mounts higher. Many microorganisms are involved in the tree decay process. Hymenomycetes are important, but so are the bacteria and nondecay-causing fungi. The expanded concept of tree decay includes the living tree and its many survival tactics, and the many tree pathogens and their survival tactics, and the constant affects of the changing environment. Tree decay is one of the most complex subjects in nature, especially when we consider the 3 tree concept, and the tree as a "community center."