Genetic Variances of Scotch Pine: Environment and Age Effects

Abstract Genetic and environmental variances of ornamental traits in Scotch pine families were examined under the influence of replication at nine locations and at three ages. The family components of variances in needle color, needle length, height, branch angle, branch length, number of branches, and crown taper were all significant, and location effects were generally larger than family effects. The family-by-location interaction variances were relatively small for height and needle traits, but were much more important for the others. Degree of genetic control was higher for needle characteristics than for height, branching habit, or crown taper. The need for replication in space and time will depend on which traits are to be improved and on the design of selection or testing schemes. Forest Sci. 21:330-339.