縄文杉
Jomon Sugi is a named Japanese cedar in the mountain forests of Yakushima. Its broad, uneven trunk and spreading limbs make it one of the island’s best-known ancient trees. Its hollow centre complicates dating, and observation decks were introduced to protect the ground around its roots.
Jomon Sugi names an individual tree; Yakusugi is a local age-based term.
A 2022–23 survey lists a height of 22.2 metres and a trunk circumference of 16.1 metres.
A hollow centre complicates dating, while observation decks help separate viewers from the ground around its roots.
The species is Cryptomeria japonica, conventionally called Japanese cedar in English. On Yakushima, naturally growing sugi at least a thousand years old are called Yakusugi; younger trees are called Kosugi. These local age terms do not divide the trees into separate species. Jomon Sugi is the name of one individual.
The Kyushu Regional Forest Office’s 2022–23 survey gives Jomon Sugi a height of 22.2 metres, a breast-height circumference of 16.1 metres and a site elevation of 1,328 metres. Circumference measures a circuit around the trunk; it is not the distance straight across it.
Circumference goes around the trunk; it is not the diameter across it. Figures are from the 2022–23 survey.
The trunk is thick and deeply uneven, with substantial branches spreading into the surrounding forest. The town’s guide relates its squat form to the harsh mountain conditions in which old Yakusugi grow. It presents a very different shape from a straight, uniform timber tree.
The survey records woody plants growing on Jomon Sugi separately from the surrounding trees and shrubs. These tree-dwelling plants include other sugi. Looking at the old tree therefore also means looking at plants supported by it and the forest growing around it.
Tree rings can preserve a record of growth, but Jomon Sugi has a hollow central core. The oldest material is difficult to obtain, preventing a straightforward count through a complete sequence of rings. The town’s guide identifies this hollow as a reason precise dating is difficult.
The Forestry survey page keeps reported ages reaching 7,200 years separate from an inference based on published data from cross-sections of Yakusugi wood. The latter lists a range of 1,300–3,600 years and a median of 2,400. These figures represent different estimates; the median is not a direct measurement of the individual tree’s exact age.
Yakushima experienced extensive logging in the Edo period. The town’s guide explains Jomon Sugi’s survival through its irregular, commercially unsuitable form. Old trees and evidence of past felling place this individual within the island’s forestry history.
The town dates the tree’s public introduction to 1966. A national tourism interpretation records that island resident Iwakawa Teiji called it Oiwasugi, before the name Jomon spread through a newspaper account. The reference to prehistoric Jomon Japan conveys antiquity; the name and the scientific estimates of age are separate matters.
A 1983 Environment Agency poster showed a local high-school student beside the trunk. The national interpretation connects that campaign with growing interest in visiting the tree. The ground beside a celebrated trunk is also where roots grow, turning the location of viewers into a conservation concern.
A wooden observation deck was built in 1996 to protect Jomon Sugi from pressure associated with increasing visitor numbers. Keeping viewers at a designated observation point reduces direct movement over the ground around the roots. Protection became part of how people approached and looked at the tree.
The Environment Ministry records the opening of a north-side deck on 1 April 2017. Its view differs from the southern viewpoint: branches and surrounding shrubs frame parts of the trunk, and a substantial spreading limb becomes prominent. Different angles reveal different relationships between the tree and its forest setting.
Jomon Sugi stands inside Yakushima’s World Heritage area. Inscribed in 1993, the property covers a defined region from the island’s centre toward the western coast, including vegetation changing with elevation and natural sugi forests. The famous tree helps people recognize that landscape, whose value also includes the surrounding plants and habitats.
No. It is a local term for naturally growing sugi at least a thousand years old. Jomon Sugi names an individual Cryptomeria japonica.
The circuit around the trunk at breast height, not its diameter. The same survey lists a height of 22.2 metres.
The hollow centre makes the oldest growth material difficult to obtain, and estimates use different evidence. Neither a published range nor its median is an exact whole-tree age measurement.
Trampling associated with increasing visitors. A designated viewing position reduces direct movement over the ground around the roots.
No. It is a defined forest landscape with varied vegetation and habitats. Jomon Sugi is one named tree within it.