光皮桦幼林生长节律的观察研究

Studies on Observation of Growth Rhythm of Young Betula luminifera

10 Betula luminifera trees were chosen from biennial forest as test material in Zhentou Forestry Station,Jixi County,Anhui Province,from March to October in 2004.Every 10 days from March 10 on the indexes of growing characteristics were investigated,such as the leading shoot,the length of side shoot and thick degree,etc.The results showed the growth rhythm,lots of leaves forming in the middle of March,flower blooming at the last ten days of March and the first ten days of April,the fruit becoming mature in May,leaves falling in the first ten days of November.During one year’s growing period,both the leading shoot and diameter breast height of B.luminifera had three obviously living period,appearing respectively from the beginning of May to the last ten days of May,from the last ten days of June to the middle of July and from the middle of August to the beginning of September,among them the increment in the second period was the largest,the third was the least one.The increment in the 3 periods took the main proportion of the whole year.This paper purposed to put forward effective feasible technological measure for nurturing management of young stand.