To provide a selective lumbering method for material wood which is good in drying efficiency by discriminating the drying difficulty of the material wood based on a threshold value and lumbering material wood difficult to be dried into a board instead of a square bar and can obtain a dry product excellent in efficiency, yield, and quality since the occurrence of a defect during drying is suppressed.

Before lumbering the material wood, the weight, length, and diameter of the material wood are measured. The volume of the material wood is obtained from the measured length and diameter. The total dry weight of the material wood is obtained from the volume and total dry specific gravity of the material wood. The water content of the material wood is obtained from the total dry weight and the weight of the material wood. The obtained water content is compared with the threshold value of a water content unsuitable for the angle picking of the material wood set on the basis of an empirical rule etc. When it is lower than the threshold value, lumbering in which the angle picking of the material wood is carried out mainly is performed. When it is higher than the threshold value, the blanking lumbering of the material wood is carried out.