Drying Procedures for Bacterially Infected Northern Red Oak Lumber.

This paper gives the results of more recent research to derive satisfactory procedures for drying infected 4/4 red oak under conditions milder than kiln schedule T4-D2. This research followed principles of kiln schedule development in response to drying strain outlined by McMillen whereby three factors affecting drying stresses must be considered: Temperature, relative humidity, and time. Successful development of a schedule depends upon determining the optimum combination of the three factors during drying lumber from green to final moisture content (MC). Surface and end checking, honeycombing, and ring failure result from shrinkage stresses caused by drying wood below the fiber saturation point. Prolonged exposure to excessive temperature while any of the wood is above the fiber saturation point weakens the wood and increases its susceptibility to interior checking and collapse.