Building Walls and Breaching Walls: Truth and Consequences in Wound Compartmentalization.
Frank S. Santamour, Jr.
Abstract: Many trees have the genetic potential to wall off wound-induced wood discoloration from moving into their interiors. These trees actually build walls, mainly of phenolic compounds, that retard the spread of microorganisms. To build these walls, they use carbohydrate reserves from their sapwood parenchyma cells interior to the wound. New wounds that breach old walls of strong-compartmentalizing trees, or wounds that intrude into discolored areas of weak-compartmentalizing trees expose areas depleted of carbohydrate content. Here strong new walls cannot be built. The amount of decay resulting from breaching old walls is greater in weak-compartmentalizing trees. Wood-discoloring microorganisms can penetrate Wall 4 when weak-compartmentalizing trees are re-wounded outside this wall. Thus, while any accidental or intentional wounding of tree trunks may result in potential decay problems, any intentional re-wounding, especially when these wounds penetrate through established walls, definitely will lead to decay. Such practices should be discouraged.