A Japanese useful tree: Castanopsis

by M. Yamanaka


Do you know Castanopsis? In Japan, shizoku is tree that has been important from primitive ages. I think, you will not surely know well because it is too common and unremarkable. For example, in Kochi, it is a major cover tree of the surrounding mountains. Moreover it is used frequent as a roadside tree. (See Use for details.) But I think it comes down to the fact that it has been used so much from ancient times that it familiar: Castanopsis is very useful tree.

Description & Taxonomy

All Castanopsis is evergreen arboreal vegetation of the Fagaceae. Castanopsis is a dominant species of hilly country areas, a low mountain place, etc. And Castanopsis is dominant species most in the broad-leaved evergreen forest belts of western part of Japan. Japanese Castanopsis has two varieties that grow wild. One sort is C. sieboldii. Another one is C. cuspidate. They distinguished in the following respects. Compared with C. cuspidata , the direction of C. sieboldii is a long and slender nut. A vertical crack is produced in a bark. etc…

Range & Ecology

There are about 100 varieties of Castanopsis found mostly in Asia. Japan is the northern distribution limit of Castanopsis. C. sieboldii is widely distributed over the warm-temperate zone west of Fukushima, and grows up into it well with a coast background. This wood is hard and since it is strong,it becomes a big tree easily. It is highly resistant to damage from salt water because leaf is thick and the cuticle layer is developed. Therefore it is almost always found near the coast.

On the other hand, C. cuspidata is mainly distributed over the inland west of Kinki district. This is more distributed over inland. Both varieties have many common features and have some which are considered to be a case where distinction is difficult. These have also found the hybrid and there is what has difficult distinction.


We can eat their Acorn. It is used for a country child’s snack in years past. Even now, it is sold at the night stall of a festival in Hakata. But, in ancient times, especially the Jomon period (about 14,000 BC to about 300 BC), it was a very important food in part because of its taste. Acorns generally have an astringent taste, but Castanopsis acorn are not astringent.

The wood is used as building materials, and it can use as charcoal. In addition the wood is used for shiitake mushroom cultivation.

Finally, the bark is used for dye. It is used for dyeing a wooden plate. If it uses together with iron nail, it will dye black.

As the only fault, honey produced near stands of Castonopsis has a bad smell and it is disliked by the apiarist. But it seems that a nature is also useful since an insect swarms around a flower well.


C. cuspidata and C. sieboldii are can see easily in Kochi. The beginning of spring,it is soft green. The flower of thin yellow is well conspicuous even from a distance. When autumn comes, you can go to gather acorns or the shiitake mushroom which grew in the dead tree of Castanopsis may be able to be found. And we can also eat.

However, if you find mushrooms that you don’t know well, it is dangerous, don’t take them. If you decide to gather them, please take care and enjoy yourself. Although it is promising with any time, I recommend you spring and autumn in this way.