Tracheid Length Variations within and among Trees in Plantation of Masson Pine Radical variation in growth ring width and tracheid dimensions of Metasequoia glyptostrobides GEOGRAPHICAL VARIATION AND CORRELATION IN SPECIFIC GRAVITY AND TRACHEID LENGTH OF JUVENILE WOOD OF MASSON PINE VARIATION OF WOOD PROPERTIES WITHIN TREES OF CHINESE FIR II.VARIATION OF TRACHEID MORPHOLOGY PRELIMINARY STUDY ON WOOD PROPERTIES VARIATION OF LOBLOLLY PINE VARIATIONS IN TRACHEID FORMAL FEATURES OF PINUS TABULAEFORMIS CARR The Probability Distribution and Sampling Simulation of the Tracheid Length in Masson Pine Variation of Wood Basic Density and Tracheid Length of Different Provenances of Loblolly and Slash Pines