Abstract: A lumber production machine and method for processing lumber uses a pressure vessel that can accommodate untreated lumber and an injection pipe disposed in the pressure vessel that is capable of injecting saturated steam into the pressure vessel. A pressure gauge is operatively coupled to pressure vessel to determine the pressure inside the pressure vessel. There is a mechanism for setting a minimum and maximum pressure inside the pressure vessel. Solenoid valves control injection of saturated steam from the injection pipe into the interior of the pressure vessel. A controller opens the solenoid valves when the minimum pressure is reached and closes the solenoid valve when the maximum pressure is reached. The method includes pressurizing and heating the lumber products with saturated steam by varying the pressure to achieve a uniform temperature inside the lumber.