STUDIES ON PHYSICAL AND MECHANICAL PROPERTIES OF DAHURIAN LARCH-WOOD OF TWO WOOD COLOURS

Dahurian1archLarixgmelini(Rupr.)Rupr.jisamaintimbertreespe-ciesinDaxing'anLingForestRegion,and'itisalsoafast-growingandregenerationtreeinNorthChina-Becauseitsecologicalamplitudeisverywild,therearemanyva-riabletypesinvarioushabitats.Themostsignificativetypes,whichhavebeenfoundrecentlyininvestigation,aretheredwoodandwhitewood.Theformerisfromyellow-browntored-brown,andthelat-tCrisfrompaleyellowtowhite.Theyaresimilarto'Redscotchpine#and'Whitescotchpine#.Theparametersofwoodcol-ourandphysico-…

Studies on physical and mechanical properties of dahurian larch-wood of two wood colours

Dahurian larch growing in Daxing’an Mountains can be divided into two types according to the wood colour: one is red, the other is white. Based on the national standard of the “Testing methods for physical &mechanical properties of wood”, the parameters of wood colour and physico-mechanical properties of the above two different woods were tested and analyzed. The result showed that the colour rational phenetic parameters, physico-mechanical properties and work abilities of the two woods were quite different, combined with the other morphological characteristics, they belong to intraspecific two different types of Dahurian larch. The white wood is superior to the red one as a valuable timber tree. Because the coefficients of shrinkage, hardness and colour of both are different, they were mixed working in the past, inevitably there have been various defects in working. In order to overcome these defects, we propose that the departments of wood production, salesmen and consumers should use them differently according to their individual character. TheProjects Supported by the Natural Science Fund of Heilongjiang Province