Abstract: The growth characteristics of height, root collar diameter and lateral branch of 5-year-old Bretschneidera sinensis trees were investigated. The results indicated that the averages, max, minimum of height and root collar diameter were respectively 2.0 m, 3.4 m, 0.5 m and 3.2 cm, 9.5 cm, 0.5 cm.The growth distributions of height and root collar diameter kept to the normal distribution. The growth of height and root collar diameter were evenly differentiated in treelet group. The current growth of height and root collar diameter of 1 to 5-year-old trees showed that the growth of height was lower in 3-year ago and higher at the 4 and 5-year. The growth of root collar diameter was bigger in the first year. The young trees which height were less than 2.0 m were not found lateral branch growth and their crown diameter was narrow and height growth was slowly.

Key words: Bretschneidera sinensis, treelet, growth characteristic, normal distribution

摘要： 研究了5 年生钟萼木幼树株高、地径连年生长、侧枝分生特性。结果表明，调查群体5 年生株高、地径平均值、最大值与最小值分别为2.0 m、3.4 m、0.5 m 和3.2 cm、9.5 cm、0.5 cm；群体幼树株高、地径生长分布遵循正态分布；幼树群体的株高、地径生长在早期表现显著的遗传分化。1～5 年生幼树的株高、地径年生长量表现为：株高在前3 年表现较低生长量，第4、5 年明显加快；地径在第1 年生长量占比较大。幼树株高小于2.0 m 的个体未发现分生侧枝，冠幅小且高生长较缓慢。

关键词: 钟萼木, 幼树, 生长特性, 正态分布