Some characteristics of growth and wood quality in Fraxinus mandshurica var. japonica
1999
Iizuka, K. (National Forest Tree Breeding Center, Ebetsu, Hokkaido (Japan). Hokkaido Regional Breeding Office) | Ubukata, M. | Oribe, Y.
To examine for wood quality the possibility of breeding on Fraxinus mandshurica var. japonica, the characteristics of growth, basic density and green moisture content were investigated in clonal plus-trees, natural trees, and planted trees. Tree heights and diameters at breast height showed a significant clonal variation, and indicated the possibility for evaluation at an earlier period of growth. The planted trees showed fast radial growth and high basic density, but the natural trees presented small annual ring width and low basic density. The relationship between annual ring width and basic density varied among individual trees. This result indicates that Fraxinus mandshurica var. japonica provides the possibility that it may be bred for growth and basic density. While, the average values of the heartwood's and sapwood's green moisture content measured at breast height level ranged from 68% to 106% and from 41% to 54%, respectively. All of the sample trees showed wet heartwood within them, and trees whose heartwood showed green moisture presented larger variations then those of sapwood. The position of frost cracks showed heartwood with green moisture content, and the green moisture content of the heartwood and the sapwood showed a remarkable difference
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