The wood siding system has air circulation gaps between overlapping siding boards and between the siding boards and a supporting wall. The wood siding system has the appearance of old-fashion clapboards; a limited flexibility that closely imitates a solid wall, and metal retainers with installation gauge, and lips and ridges to control the direction of shrinkage and swelling of the wood boards to preserve the visual appeal of the wood siding. A wood grain pattern on the front surface of each siding board is a mirror image of a wood grain pattern on the front surface of another siding board.