Currently, the natural forest, which has not been touched at least since the the field practice forest opened covers 2,150 ha, approx, half of the total area of 4,200 ha of this research forest, and there are virgin forests within it that are considered to be untouched by humans ever since the forest was formed.
現在、当研究林の総面積4,200haの約半分に当たる2,150haは少なくとも開設後は手の入っていない天然林で、この中には森林の成立以降人為的な力の加わっていないと考えられる原生林がある。