Abstract: In the course of studying Betula luninifera community at Weimin in Fujian Province,the interrelation between the growth rate of B.luninefera and its neighborhood interference index has been analyzed and the relation of its size,neighborhood interference index and growth rate has been found.The results show that the influence of neighborhood interference index and growth rate has been found.The results show that the influence of neighborhood interference becomes weak gradually among the investigated trees whose breast height diameter is over 10cm.So it is suggested that B.luninefera at Weiming should be forested before the breast diameter reaches 10cm.

Key words: tillage, soil bulk density, soil organic carbon, crop yield, water use efficiency.