Effect of age on the variation, correlations and inheritance of selected wood characteristics in black spruce (Picea mariana)

Summary The variation, correlations and inheritance of various intraring wood characteristics in 15-year-old black spruce (Picea mariana) trees from 40 half-sib families grown in New Brunswick were examined. The emphasis was placed on the effect of age on these genetic parameters. With increasing (cambial) age, ring width and ring density tend to exhibit a constant tree-to-tree variation whereas most other characteristics exhibit a smaller tree-to-tree variation. The heritability for latewood characteristics does not seem to change appreciably. Other characteristics (except RDmi), however, tend to be less heritable when the tree grows older. Correlations between ring density and most intraring characteristics tend to be weaker with increasing age. This implies that fast-growth in this species will have less negative effect on wood density when the tree grows older.The author wishes to thank Dr. E.K. Morgenstern of the Genetic Resource Consultants, Permbroke, Ontario and Mr. D. Simpson of the Canadian Forest Service in Fredericton, New Brunswick for their involvement in the initial planning of this project. Thanks are also due to G. Chauret, T. Keenam, R. Ploure, V. Steel and C. Reitlingshoefer for their technical assistance.