The purpose of this study was to identify optimum fertilization technology for Neolitsea sericea and Cinnamomum yabunikkei, which are major species of broad-leaved afforestation trees. Depending on the treatment of water soluble fertilizers (N:P:K = 19:19:19, v/v/v), changes in root collar diameter, plant height, dry weight, and seedling quality index were measured as growth characteristics and changes in photochemical efficienty and chlorophyll content as physiological characteristics. After analyzing growth characteristics the highest root diameter and plant height growth were observed in 1.5 gL concentration in the case of N. sericea, and 1.0 g･L-1 in the case of C. yabunikkei. The H/D ratios in these fertilizer concentrations showed 7.0 cm･mm-1 for N. sericea and 9.3 cm･mm-1 for C. yabunikkei, which were significantly higher than any other concentrations. N. sericea and C. yabunikkei had high total dry weight, 5.92 g in the 1.5 g･L-1 treated area, and 6.01 g in the 1.0 g･L-1 treated area, respectively. The T/R ratio and seedling quality index were also significantly higher in the fertilization treatment area of high dry weight. As a result of analysis of physiological characteristics the photochemical efficiency and chlorophyll content were lower than those of healthy leaves in both species, with high values of 1.5 g･L-1 in the case of N. sericea, and 1.0 g･L-1 in the case of C. yabunikkei. According to the overall results of this study, the optimum fertilization level varies depending on the nutritional needs of respective species, and the fertilizer application rates of water soluble fertilizer suitable for the production of 2-year-old containerized seedling of N. sericea and C. yabunikkei were 1.5 g･L-1 and 1.0 g･L-1, respectively. However, it is difficult to predict the adaptation characteristics of the trees to long-term changes when using fertilizers, because this study is the analysis of the short term responses from 2 year old young seedlings. In addition, they are cultivated in greenhouses or nursery field; in this case, it is believed to be necessary to study the response of trees to rapid changes of future climate. Additionally, since the response to fertilizer concentration varies greatly depending on the tree species, it is necessary to continuously study major tree species in Korea and other species that are sensitive to climate changes.

Introduction
 Methods
  Test site and species
  Treatment with a fertilizer
  Growth and physiological characteristics
  Physiological characteristics
  Statistical analysis
 Results and Discussion
  Growth characteristics
  H/D ratio
  Dry weight
  T/R ratio and seedling quality index (SQI)
  Physiological characteristics
 Conclusions
 References

• Eon-Ju Jin(Southern Forest Resources Research Center, National Institute of Forest Science)
• Min-Gi Cho(Southern Forest Resources Research Center, National Institute of Forest Science)
• Hak-Gon Kim(Gyeongsangnam-do Forest Environment Research Institute)
• Kwang-Soo Lee(Southern Forest Resources Research Center, National Institute of Forest Science)
• Eun-Ji Bae(Southern Forest Resources Research Center, National Institute of Forest Science) Corresponding author