Anatomical, physical, and mechanical parameters of clone plantation tree, Cunninghamia lanceolata

Abstract

Anatomical characteristics of the plantation tree, Cunninghamia lanceolata were studied. Clonal variability and intra-tree variation, as well as its possibilities of application to the wood industry were analyzed for four clones. Tracheid length from the first to 17th annual ring within clones increased rapidly at first, and then plateaued. The maximum value appeared at the 14th annual ring of clone IV (3795 μm), and the minimum value appeared at the 1st annual ring of clone I (849 μm). Tracheid width and tracheid double wall thickness increased first and then tended to be flat or slightly decreased; tracheid length to width ratio showed an overall increasing trend; the variation of tracheid double wall thickness was not significant. Between clones, the variation coefficient of tracheid width, double wall thickness, and wall to cavity ratio were large. The tissue proportion within clones from large to small was the following: tracheid proportion > wood ray proportion > parenchyma proportion, and there was no significant difference between clones. The basic density within clones showed a gradual increase but a certain fluctuation; the difference between clones was not significant. The maximum crystallinity appeared in clone II (sapwood 55.1%, heartwood 51.2%), and the difference between clones was not significant.