The vegetation dynamics of Korean red pine (Pinus densiflora) forests were investigated at Mt. Seorak, Korea. Our Detrended Correspondence Analysis (DCA) classified the forests into four types: ridge top, upper slope, lower slope/hill, and streamside. The ridge top forests were likely to sustain themselves, as suggested by the large proportion of seedlings and saplings (89% at <25 years old) and the relatively high density ofP. densiflora (2388 stems ha^-1). Periodic disturbances, such as flash floods, made the streamside inhospitable to late-successional species. Such conditions may have provided a favorable environment for the recruitment ofP. densiflora seedlings through increased solar radiation and decreased competition with other species. On the upper slopes, the dominance ofQuercus seedlings and saplings (63% at >25 years old, and a density of 3263 stems ha^-1) suggests a transition from pine to oak forest. Extensive human interventions appeared to arrest the natural succession from pine to oak forests on the lower slope/hill, while encouraging invasions by forest-edge and introduced species (e.g.,Rosa multiflora andRobinia pseudoacacia).