Effects of Different Trunk Buried Depth on Growth and Biomass of One-year Old Catalpa bungei

[Objective] To understand growth and biomass of one-year old Catalpa bungei cl.'Yu-1'under different trunk buried depth.[Method] Four trunk buried depth were designed(10,20,30 and 40 cm),and among each treatment three standard trees were selected,and then their branch number,length and coarseness were investigated,and meanwhile the diameter,height,above and underground biomass were measured.[Result] Among four treatments,the branch amount,length and width had no significant difference of one-year old Catalpa bungei cl.'Yu-1'.The average branch number,width was biggest under 10 centimeter,and the average branch length was the longest under 30 centimeter.The diameter and tree height decreased with buried depth increased.The differences of above-ground biomass,stem biomass and branch biomass among treatments were extremely significant,the differences of root biomass was significant.Above-ground biomass and root biomass decreased with buried depth increased.[Conclusion] There were different influences on diameter and biomass among four trunk buried depths,diameter and biomass were biggest when trunk were buried under 10 centimeter.