The forest of Korea had been severely degraded since early 1900s until 1950s. Korean Government has successfully accomplished the reforestation works since 1960s. However, some plantations showed poor survival and growth caused by ignoring site characteristics in selecting plantation species and lack of tending works such as thinning. The natural regeneration of indigenous species, such as Quercus species and Pinus densiflora Siebold & Zucc., were examined in the plantations of Pinus koraiensis Siebold & Zucc. and Larix kaempferi Fortune ex Gordon. Quercus species regenerated mainly by sprouting while P. densiflora regenerated naturally from a few mother trees that remained in the plantations. P. koraiensis showed poor survival (IVI ≤ 25%) and suppressed growth (height ≤ 3 m and DBH ≤ 3 cm at 20 year-old) by Quercus species or P. densiflora in the plantation areas, however had high survival (IVI ≥70%) and growth (8 m height and 14.1 cm DBH at 20 year-old) in areas where silvicultural practices were conducted. L. kaempferi showed good survival (IVI ≥40%) and growth (17.2 m height and 16.3 cm DBH at 30 year-old) mostly in valley areas, while it was nearly dead (IVI ≤ 10%) in ridge or ridge-slope areas and was replaced by indigenous species such as Quercus species (IVI ≥ 25～55%) or P. densiflora (IVI ≥ 18～50%).

ABSTRACT
 I. INTRODUCTION
 II. Materials and Methods
  2.1 Study site
  2.2 Methods
 III. Results and Discussion
  3.1 Species composition
  3.2 Stand structure
 IV. Conclusion
 ≫ Literature cited

• YeongDae Park(Research Institute for Agriculture and Life Sciences, Seoul National Univ.)
• DonKoo Lee(Dept. of Forest Sciences, College of Agriculture and Life Sciences, Seoul National Univ.)
• SeonDeok Choi(Dept. of Business Development & Planning, National Forestry Cooperative Federation)
• SoonDuk Kwon(Div. of Carbon Sink and Forest Res. Manage., Korea Forest Research Institute) Corresponding author