一幸 小田

Green moisture content and basic density of 95 woody species growing in Kyushu University Forests, Japan

We investigated the green moisture content and basic density of 95 woody species growing in Kyushu University Forests. In softwood species, the green moisture content of heartwood ranged from 28% in Cryptomeria japonica to 67% in Abies firma, and in sapwood, from 75% in Tsuga sieboldii to 160% in Cryptomeria japonica. The green moisture content of softwood trees was greater in sapwood than heartwood. The green moisture content in the heartwood of hardwood species ranged from 34% in Euonymus alatus f. striatus to 83% in Kalopanax pictus, and in sapwood, from 45% in Fraxinus sieboldiana to 153% in Actinidia polygama. We found three radial variation pattern types in stems of hardwood species. The green moisture content was higher in heartwood than sapwood, in the first type, whereas in the second, it was higher in sapwood than heartwood. In a third type, differences between heartwood and sapwood were relatively small. The basic density of softwood species ranged from 378 kg/m3 in Cryptomeria japonica to 524 kg/m3 in Tsuga sieboldii. Most trees tended to decrease in basic density from corewood to outerwood. Basic density in hardwood species ranged from 266 kg/m3 in Paulownia tomentosa to 751 kg/m3 in Rhaphiolepis indica var. umbellata. We identified three types of radial variation pattern in stems of hardwood species. In the first type, basic density was higher in corewood than outerwood, whereas in second, it was higher in outerwood. In the third type, differences between corewood and outerwood were small. We also provided the information on the age and size of heartwood formation. Keyword:green moisture content; basic density; Kyushu University Forests; Japan

Relationship between Wood Anatomical Properties and Specific Permeability of Sugi (Cryptomeria japonica) Sapwood and Intermediate Wood

The objective of this study was to clarify anatomical factors which determine specific permeability of sapwood and intermediate wood in air-dried sugi (Cr?~ptomeria juponica) wood. Superficial air permeability of sugi sapwood and intermediate wood was measured and then specific permeability was determined. Using these specimens for permeability tests, the proportion of latewood and earlywood, the percentage ol aspirated and incompletely aspirated pits, the number of bordered pits per tracheid, the number of tracheids per unit area and tracheid length were obtained. Specific permeability decreased with increasing levels in the stcm except for the lowest level and also related to distance from pith, suggesting that cambial age is related to specific permeability. A clear relationship between percentage ol latewood and specific permeability was not found, suggesting that effective pathways in earlywood determines permeability. Specific permeability of intermediate wood and sapwood were significantly related to the number of effective open pits in earlywood, Mi3J, which was determined by anatomical properties such as aspirated and incompletely aspirated pits, the number of pits and tracheids, and proportion of latewood, suggesting that specilic permeability of sugi sapwood and intermediate wood is a physical value determined by the intrinsic properties of earlywood in addition to the condition of bordercd pits.