A method for selecting random length boards for nesting into a single row of predetermined lengths includes the initial step of arranging a plurality of random length boards on an accumulating rack. A plurality of the boards are then conveyed to channels in an adjacent storage rack. The length of each board is determined as the board is conveyed from the accumulating rack to the storage rack, and this information is transmitted to a central processor. The processor calculates combinations of board lengths in the storage rack which will form a single stock row having a combined board length within a predetermined target range. The processor then selects a preferred combination of boards from the possible combinations, and activates gates in the channels to drop the boards to a conveyor and move the selected boards to a stock row accumulating location. The processor then activates gates on the accumulating rack tracks to convey additional boards to empty channels in the storage rack, and repeats the process. The apparatus includes an accumulating conveyor with longitudinal tracks positioned adjacent a storage rack with longitudinal channels aligned with the tracks. A scanning assembly is positioned between the accumulating conveyor and storage rack for scanning boards moving between the conveyor and storage rack, to determine the length of each board. The central processor is connected to the scanning assembly, and gates on the accumulating rack and storage rack, to automatically operate the system.