The response of four tree species, Metasequoia glyptostroboides Hu et Cheng, Chamaecyparis obtusa Sieb. et Zucc., Quercus serrata Murray, and Quercus myrsinaefolia Bl. to wound made at different seasons were investigated. In all species, wound-induced discoloration extended further in the axial direction with increasing time after wounding, the tangential extension was strongly restricted. Wounding during the growing season (spring and summer) resulted into longer discoloration during the first 2 months, however, discoloration by winter and/or fall wounding extended longer than those of summer wounding after 6 months. In all tree species examined, the wound closure after 6 months was conspicuously slower in fall wounds compared to other seasons. From the results, wood discoloration lengths varied greatly between seasons of wounding, however, the difference tended to decrease after longer period. Wound closure was conspicuously slower for fall wounding compare to other seasons.