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We quantified biomass accumulation and nitrogen (N) retranslocation,allocation,and utilization of Changbai larch (Larix olgensis) seedlings subjected to four fertilization treatments (24,59,81,117kg·ha-1 N) with an unfertilized control during summer and autumn 2009.Ammonium phosphate (18-46-0) was the fertilizer used in all treatments.On both sampling dates,the needles had greater biomass and N content than new (2009) stems and old (2008) stems,and coarse,medium and fine roots (diameters of ＞5,2-5 mm,and 0-2 mm,respectively).Higher N concentration was observed in old stems and coarse roots than that in new stems and medium roots.In mid-summer,fine roots had higher N concentration than coarse roots.The treatment with 24 kg·ha-1 N had the greatest biomass and N content in needles and old stems,and highest net N retranslocation (NRA) and amount of N derived from soil.On September 21,no N translocation was observed,while the treatment with 24 kg·ha-1 N had the highest N utilization efficiency and fertilizer efficiency.Vector analysis revealed that all four fertilization treatments induced N excess relative to the control.The treatments with 59,81,117 kg·ha-1 N induce N excess compared with treatments at 24 kg·ha-1 N.We conclude that the traditional local fertilizer application rates exceeded N requirements and N uptake ability for Changbai larch seedlings.The application rate of 24 kg·ha-1 N is recommended.