Publisher: University of Vermont Extension

The area of stained sapwood associated with tapping or other wounds in maple trunks has long been interpreted to represent the area of wood that is compartmentalized, and thus unavailable for sap flow. We tested this interpretation by passing dye through maple stems that had been tapped and observing the area that was blocked. Our results indicate that the blocked portion of the trunk associated with a wound taphole is somewhat larger than the area which is visually compartmentalized (stained).