Establishment of Individual Basal Area Growth Model of Korean Pine

The influence of Hegyi's competition index(CI) on the basal area increment(BAI) of Korean pine was presented based on the stem analysis data of 62 Korean pine trees from Jingouling Experimental Forest Farm of Wangqing Forestry Bureau,China.The results showed that only the index of the height at 5 years ago was significantly correlated with BAI among the 7 variables(tree age at 5 years ago,DBH at 5 years ago,height at 5years ago,height to the live branch,height to the death branch,live crown length and CI),and it entered the model rather than the left indices.