Chemical behavior and distribution of boron species in Japanese cedar (Cryptomeria japonica D. Don) specimen treated with methanolic boric acid solutions were investigated by means of weight and Raman spectra measurements. After this treatment, weight gain of the specimens was approximately proportional to the boron concentration in the range of 1.8×10^-1 to 1.1 mol/dm³. From the Raman measurements, it was revealed that the bulk of boron remains in the specimens as B (OH)₃, although a small amount of boron was emitted into air during air-drying. These results indicated that the high concentrated methanolic solutions make it possible to impregnate wood with considerably large amounts of boron in comparison with the aqueous solutions. The Raman spectra, however, suggested that boron was extremely concentrated near the surfaces of the air-dried wood specimen.

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