Wooden construction material including lumber, wood,and timber. All parts of heavy branches and tree trunks jukan 樹幹 including bark juhi 樹皮, sapwood shirata 白太 (*henzai 辺材), and heartwood jushin 樹心 (*shinzai 心材) are used. Usually, the limbs and trunk are stripped of their bark and are sawed or split into building material. However, unstripped or unbarked posts are to be found frequently used as central posts *nakabashira 中柱 of alcoves *tokonoma 床の間, especially in tea ceremony houses *chashitsu 茶室. Mokuzai have two basic categories: coniferous or evergreen trees shinyōju 針葉樹, and deciduous or broad-leaf trees kōyōju 広葉樹, which lose their leaves in the winter. Timber from conifers is used mainly for structural purposes while timber from deciduous trees is especially suitable for finishing.