Canadian Forest Service Publications

Hierarchial analysis of black spruce and balsam fir wood density in Newfoundland. 2015. Groot, A.; Luther, J.E. Canadian Journal of Forest Research 45(7): 805-816.

Year: 2015

Issued by: Canadian Wood Fibre Centre

Catalog ID: 39047

Language: English

Availability: PDF (request by e-mail)

Available from the Journal's Web site.
DOI: 10.1139/cjfr-2015-0064

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We used a hierarchical approach to examine patterns of black spruce and balsam fir wood density across Newfoundland. Wood density measurements were aggregated at ring, tree, and plot levels. Portions of the variance in wood density at the different levels were explained by predictor variables at multiple levels of a forest structural hierarchy (ring-, tree-, and plot-level variables). Hierarchical fixed effects models accounted for 39%, 61%, and 86% of the variance in wood density of black spruce at ring, tree, and plot levels, respectively, with RMSE values of 62.7, 34.6, and 19.4 kg·m−3. Corresponding models accounted for 31%, 38%, and 63% of the variance in wood density of balsam fir, with RMSE values of 62.4, 35, and 16.7 kg·m−3. The hierarchical analysis demonstrated consistent negative associations of wood density to radial growth rate at ring, tree, and plot levels of aggregation. Variables that act as surrogates for radial growth are thus important for understanding patterns of wood density at higher scales and for the practical application of mapping wood density across landscapes.

Plain Language Summary

The objective of this work was to look at wood density from the perspectives of tree growth rings, of trees within forests, and of groups of trees in forests. Wood density is an important wood property that affects the quality of lumber and paper products. The researchers measured the density of wood samples taken from black spruce and balsam fir trees across the island of Newfoundland. They also measured characteristics of tree growth rings, of individual trees and of groups of trees. Wood density generally was lower in wider annual rings, in trees with greater diameter growth and in groups of trees with greater diameter growth. Wood density was generally higher in annual rings near the centre of the tree, and in both individual trees and groups of trees with smaller diameters. The study also showed that climate may have some influence on wood density. These results increase our understanding of wood density in balsam fir and black spruce, and will make it possible to improve prediction of this important wood property.