The arboretum is taking shape thanks to the efforts of the officials and employees of the Ogasan Natural Reserve Management Company.

The area is located in a place where the northern distribution boundary line of broad-leaved woodland meets the southern distribution boundary line of needle-leaved woodland. The arboretum consists of five main districts and other districts suited to natural and geographical conditions of the Mt. Oga area and the characteristics of plant distribution.

All sorts of woody plants growing in the reserve are being transplanted in the main districts according to their heights above sea level.

And several districts for introducing new species of plants and the medicinal herbs fields are being made.

Various plants absent in the Mt. Oga area are being planted in the districts for introducing new species of plants including the wild fruit-bearing plant district and oil-bearing tree district.

Wild insam, Epimedium Koreanum, balloonflower, etc are striking roots in the medicinal herbs fields.