Abstract:

In order to study the differences of physical and mechanical properties between two new Catalpa bungei clones "Wanqiu 8401", "Wanqiu 8402" and "Jinsiqiu", three ramets of each clone were determination. The results showed that basic density, air-dried density, hardness of end surface, hardness of tangential section, hardness of radial section, bending strength, modulus of elasticity, compression strength parallel to grain, tensile strength parallel to grain, toughness, shear strength parallel to grain of tangential direction and shear strength parallel to grain of radial direction had significant differences among clones. "Wanqiu 8401" and "Jinsiqiu" were highly similar, which was significantly better than "Wanqiu 8402". Also, significant differences was obversed between mature wood and juvenile wood of three clones. Additionally, three clones were comparison with other timber which were popular in China, "Wanqiu 8401" and "Jinsiqiu" were better than Toona ciliate, but worse than Juglans mandshurica, "Wanqiu 8402" and Toona ciliata were highly similar, "Wanqiu 8401", "Jinsiqiu" and Cinnamomum camphora, Phellodendron amurense were highly similar.

Key words: Catalpa bungei, new clones, timber, physical and mechanical properties, differences