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The limited range of commercial timber species in Great Britain has led the forestry sector to consider wider planting of other species. This research addresses wood properties, particularly relevant to structural timber, of noble fir, Norway spruce, western red cedar and western hemlock in Great Britain. Sampling covered three regions to get a representative sample for the country. Bending stiffness, bending strength, density and twist distortion from drying were assessed. The results showed high yields of C16 for all these species, with Norway spruce and western hemlock performing comparatively well to typical British-grown Sitka spruce. Within this dataset, variation of mechanical properties within trees was more important than differences between species. Strength and stiffness increased with age, whereas density followed different trends in the inner and outerwood. The three properties were modelled based on ring number. The use of acoustic techniques to assess the mechanical properties of wood (in particular stiffness), was investigated in clears, sawn timber, logs and trees. The best results were found combining density with acoustic velocity in sawn timber. The use of acoustic techniques in standing trees was more reliable measuring distances of two or three metres, rather than the commonly used one metre; most likely due to a change in the wave propagation. Tree architecture was studied for timber production and quality. Noble fir described the highest merchantable taper profile. Branchiness varied importantly with height in the stem, and models were built for number, diameter and angle of branches. Western red cedar and western hemlock had fewer but thicker branches compared to noble fir and Norway spruce. Future work should produce grading machine settings and address the variation of timber quality and merchantability under different silvicultural regimes. This thesis concludes that the four species investigated can contribute to diversity the timber industry in Great Britain.

Classical dendrochronology involves using standard statistical methods, such as correlation coefficients and t-values to crossmatch undated tree-ring width sequences to dated 'master' chronologies. This crossmatching process aims to identify the 'best' offset between the dated and undated sequences with a view to providing a calendar date estimate for the undated trees. Motivated by the successful and routine use of Bayesian statistical methods to provide a fully probabilistic approach to radiocarbon dating, this thesis investigates the practicality of using a process-based forward model known as 'VSLite' at the core of Bayesian dendrochronology. The mechanistic VSLite model has the potential to capture key characteristics of the complex system that links climate to tree-ring formation. It allows simulated, dated tree-ring chronologies to be generated at any geographical location where historical climate records exist. Embedding VSLite within a Bayesian approach to tree-ring dating allows combination of both ring-width data and any available prior information. Additionally, instead of identifying the `best' calendar date estimate, the Bayesian approach allows provision of probabilistic statements about a collection of possible dates, each with a specific (posterior) probability. The impact of uncertainty in the VSLite input parameters on the model output has been systematically investigated in this thesis, and the VSLite-based approach to Bayesian tree-ring dating has been explored using both simulated and real data. Results of implementing the new VSLite-based approach are compared with those using current classical and Bayesian approaches. An option for reducing the need for preprocessing data is also investigated via a data-adaptive rescaling approach. Having established the effectiveness of using the mechanistic forward model as the core for Bayesian dendrochronology, the practicality of adopting it to aid in dating in the absence of suitable local master chronologies is also explored.