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The stiffness and strength of timber is important to industries which rely on it as a building material. As a consequence of high variability in these properties when trees are milled, timber is graded. There has been interest and research in breeding trees which reliably produce this higher value timber --ref--.  Trees are subjected to multiple environmental mechanical loads and adapt the mechanical properties of their stems to an environment changing over time. Wind is one of the most important (Timell, 1986a). Wind loading can cause mechanical failure making the tree worthless in a commercial sense. A substantial amount of research on predicting wind throw and wind damage risk for commercial species has been conducted (Ancelin et al., 2004; Peltola et al., 1999; Mayer et al., 1989; Gardiner et al., 2000; Dunham and Cameron, 2000). These models do not investigate the structural failure within the tree, but attempt to identify how likely failure is to occur in a particular environment. Wind also has less obvious effects. Continued wind loadings from a prevailing direction can cause compression reaction  wood productionon the lee side of the pith  in order to compensate for this loading (Timell, 1986a). One way of investigating the time phenomenon is the use of mathematical models. However because of the size of the tree, modelling an entire tree from the molecular level is infeasible, so homogenisation is used. This is the case for a number of current problems in plant biophysics. In order to use finite element methods experimental data is required for parametrization.