Influence of Growth Rate and Cambial Age on Density of Rauli (Nothofagus nervosa) in Relation to Vessel Lumen Areas and Numbers

To assess the likely effects of silvicultural treatment on the wood quality of Nothofagus nervosa grown in the UK, and the possibilities of independent selection within seed origins for density and growth rate, ring width and wood density were analysed from pith to bark of 19 trees. Variations in vessel lumen size, vessel number mn 2 , and total lumen area mm -2 were analysed in ten trees. Since density increased by only 0.005 g cm -3 per mm increase in ring width, silvicultural practices such as initial spacing and thinning are not likely to have a substantial effect on the wood density of rauli, Similarly, variation in density with cambial age was significant but relatively minor in the 40- and 60-year old trees of the present sample, suggesting that the rotation length is unlikely to have any practical influence on the density of rauli, Considerable between-tree differences in density were found which did not correspond to differences in ring width, suggesting it should be feasible to select independently for density and growth rate. These differences in density were associated with differences in both vessel lumen size and vessel number mm 2 .