Tree Day (Ki no Hi)

What Is Tree Day?

October 8 is Tree Day (Ki no Hi) in Japan. It was established in 1977 by the Japan Federation of Young Wood Industry Groups to promote the benefits and use of wood. The date comes from the fact that combining the kanji for ten (十) and eight (八) forms the kanji for tree (木). As autumn deepens, it is a day to think about the warmth of wood and the gifts of the forest.

Japan's Culture Built With Wood

Forests cover about two-thirds of Japan's land, making it one of the most forested countries in the world.

• Horyuji, the world's oldest wooden buildings: The western precinct of Horyuji Temple in Nara is considered the oldest surviving group of wooden buildings in the world. In 1993, the "Buddhist Monuments in the Horyu-ji Area" became Japan's first UNESCO World Cultural Heritage site. It shows that, with care, wooden buildings can stand for more than 1,300 years.
• Shikinen Sengu: At Ise Grand Shrine, the main buildings are rebuilt every 20 years in a ceremony called Shikinen Sengu. Through the rebuilding, woodworking skills have been passed down from craftsman to craftsman.
• Wooden buildings are growing taller: In recent years, materials such as CLT (cross-laminated timber), made by gluing layers of boards at right angles, have made mid- and high-rise wooden buildings possible.

Trivia About Wood in Language and Daily Life

Wood appears in many parts of Japanese language and daily life.

• Enjoying wood grain: Much Japanese furniture and joinery is left unpainted to show off the beauty of the grain.
• The scent of hinoki: Japanese cypress (hinoki) has long been used for bath buckets and bathtubs because of its pleasant scent and water resistance.
• Kanji with "tree": Besides characters that stack trees like 林 (grove) and 森 (forest), many kanji use the tree radical, such as 桜 (cherry), 松 (pine), and 杉 (cedar).

Wood Trivia

• Trees store carbon: Trees absorb carbon dioxide as they grow and store it as carbon. Using wood for homes and furniture for a long time keeps that carbon locked up.
• Tree rings record the climate: Ring widths vary with each year's temperature and rainfall, so tree rings can be used to estimate past climates or the year a tree was cut (dendrochronology).
• Mokuiku (wood education): This initiative, promoted by Japan's Forestry Agency and others, helps children develop a connection to trees and forests through wooden toys and products.
• Using domestic timber: Many of Japan's forests are cedar and cypress planted after the war, and they are now ready to be used. Using domestic wood helps keep forests well maintained.
• About disposable chopsticks: Many Japanese-made disposable chopsticks are made from offcuts left over from sawmilling or from thinned trees.

Ideas for Tree Day

• Care for the wooden furniture or tools at home by wiping them down or applying oil.
• Visit a large tree in a park or shrine and feel its bark.
• Choose products with forest certification labels, such as FSC or SGEC.
• Visit a woodworking class or an exhibition of wooden toys.

A Day to Notice the Warmth of Wood Around Us

Tree Day on October 8 is a day to appreciate the trees that support our lives as homes, furniture, and tools. While some buildings like Horyuji have stood for over 1,300 years, Japan's forests today have reached a stage where using wood helps them stay healthy. Why not touch the wooden things around you today and feel the gifts of the trees?