Mongolian oak pure forests are mainly distributed in shaded and semi shaded slopes at an altitude of 500-700 meters, mainly consisting of natural mixed forests of Korean pine cloud and fir, Korean pine ash, Korean pine linden, Korean pine green maple, and Korean pine Mongolian oak. The shrub layer includes hazelnut, hazelnut, acanthopanax senticosus, and mixed with a small amount of wild clove, mountain plum, and lespedeza. The herbaceous layer includes moss on the goatee, black water fern, crane grass, lily of the valley, and transparent bone grass. This community type can be regarded as the northern subregion of the distribution area of the Korean pine coniferous and broad-leaved mixed forest, and is the transitional vertical distribution zone from the Korean pine coniferous and broad-leaved mixed forest to the subalpine spruce and fir forest.