| The paper deals with the wood anatomical, physical and mechanical properties of 24-years-old hybrid tulip ( Liriodendron chinense x L. tulipifera) trees. The comparisons with maternal plant Chinese tulip tree and paternity American tulip tree have been made. The macroscopic and microscopic structure was described. The order cluster and main composition analysis determine the boundary between the juvenile and mature wood. The wood anatomical, physical and mechanical properties of the juvenile and mature wood are compared with variance analysis. The juvenile anatomical indexes forecast the mature anatomical indexes. Indexes between trees have carried out variance analysis. Besides, the hybrid tulip tree is compared to other common plantations such as populus, eucalypt and masson. The results show:(1) The average number of vessels is 66 /mm2, the average diameter of vessels is 57μ , the average length of vessels is 647 μm, the growth ring width is 1.72 ~ 11.93mm, the fiber length is 0.80- 1.74mm, the diameter of fiber is 20.9- 31.6μ m, the thickness of fiber wall is 16.45 - 19.20μm, the ratio of fiber length to width is 48.02 - 55.74, the ratio of double wall thickness to lumen was 0.471 - 0.789, the microfibrillar angle of fiber is 6.62 - 18.62°.(2) The air-dried density is 0.544g/cm3, the radial, tangential and volumetric shrinkage are respectively 5.06%, 9.61% and 14.91%. The longitudinal compression strength, MOR and MOE are respectively 42.1Mpa, 84.5MPa and 7.4GPa. Every value of physical and mechanical properties is between that of Chinese tulip tree and American tulip tree.(3) The order cluster analysis of main composition determine the boundary between the juvenile and mature wood from the hybrid tulip tree which was at the age of 9-11 year.(4) When the juvenile wood was compared to the mature wood, the former growth ring width larger, the microfibrillar angle, the fiber length shorter, the diameter of fiber smaller, the thickness of fiber smaller, the ratio of fiber length to width smaller, the ratio of double wall thickness to lumen smaller. T-Test values indicated that there are significant differences between the Juvenile and Mature wood. In physical and mechanical indexes, the basic density, air-dried density, compression strength parallel to grain, MOR, MOE and toughness of mature wood are higher than that of juvenile wood. The shrinkages of juvenile wood are higher than that of mature wood. By means of variance analysis, all indexes are different between the juvenile and wood except the drying shrinkage of radial direction. The results show: mature wood properties are better than juvenile wood properties.(5) The variance analysis show: the growth ring width, the basic density of the growth width, the fiber length, the thickness of fiber wall, the ratio of double wall thickness to lumen, the microfibrillar angle, the drying shrinkage of radial direction and MOE are not different among the hybrid tulip trees. The discrepancy of other index is notable.(6) The result shows: the Hybrid wood is a kind of fine plantation, when it is compared to other plantations.(7) According to the anatomical indexes, the hybrid tulip tree is a fine raw material of papermaking. According to major strength indexes, moreover, compactly structure, light-color, straight grain, easily process and little deformed. The wood is fine furniture material and interior decorative material. It can also make light structure to use material. Because the hybrid tree grows rapidly, it can be popularized.
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