Abstract: A lumber marking system for accumulating information about pieces of lumber (e.g., boards), such as grade and volume information, and marking the end of each piece with a related code is disclosed. The boards (29) are moved by a chain/lug conveyor (11) past a series of stations. A pulse generator (45) coupled to the chain/lug conveyor (11) produces a pulse for each increment of conveyor movement. The boards (29) are moved past a console (43) where a viewing operator enters grade data. The boards also moved through a curtain or optical detectors (35), which determines in segments the maximum available length of each board. The boards also pass an optical width measuring system (47) that determines the width of each board by counting the number of pulses generated by the pulse generator (45) during the period of time that a light beam is broken by each board.