It is said that the building will last 1,000 years if the cypress tree is used. Horyu-ji Temple still has a 1,000-year-old building, which tells us the heart of the carpenters in Asuka period who worked on trees and architecture. If you do not see the strength and habit of the tree, you will not be able to build a strong building ... According to the oral tradition handed down to generations, the wisdom of craftsmen who know the heart of the tree that modern architecture has forgotten and touch each other with wood and skin seems to be alive.

　There is a saying, "Buy mountains without buying trees." It is a teaching to build a tower with a tree that grew up in the same mountain. Kiso trees and trees from Nara and Shikoku are not used together. No matter how much the same kind of tree changes the environment, the nature will be slightly different, because the difference in character will eventually come to the building or cause a strain. Rather than looking at trees as one of the building materials, if you do not find the timber as a living tree that has been exposed to the rain and wind in the deep mountains, you will not be a full-fledged carpenter or ridge beam That is. On the other hand, it is also said that "Know the soil to know the tree."

　There is also a time to cut trees. It is called "Tree 6 Bamboo 8", and it seems that it is better to cut trees in June in old calendar and bamboo in August. June is the current August according to the solar history, and after this time, it is better to cut trees at this time to prepare for wintering. It is time to absorb enough nutrients and start to glue from now on. It is said that August is now October and will be cut down on a dark day. It is said that insects enter when cut on the night of the moon and night.

　The tree on the pass is strong and the tree on the middle is moderately good. The trees in the valley are soft. Depending on the direction of the mountain, the trees that grow on the north side are soft, so they are made timber, and the trees that grow in a sunny place on the south side become pillars because the material is very hard.

　Trees that look like the same have subtle habits each by one. The carpenters call this habit "the heart of the tree." It is the basis for building a building that can withstand hundreds of years of wind and snow by combining the habit and nature of trees without killing trees. This is called 'the wooden group of the tower is a wooden habit group.' A tree that always grows in a place where the wind blows from the same direction has the power to work against the wind. By making good use of that habit, if you combine the right twist and the left twist, the members will be assembled and solid. If the right twist and the right twist are assembled, the tower will twist to the right over a long period of time.