CORRELATION AMONG GROWTH, DENSITY, FIBER DIAMETER AND HEARTWOOD IN RADIATA PINE

Relationships were studied among growth traits (tree height, diameter and sapwood area), wood microstructure traits (density, fibre radial a nd tangential diameter) and heartwood formation traits (initial 5 year radius, heartwood area and number of heartwood rings) using simple co rrelations and principal component analysis, Traits were measured in a small radiata pine (Pinus radiata D. Don) diallel experiment involvin g a parent whose progeny require low energy and produce bright paper d uring thermomechanical pulping. Results indicate that some larger tree s had much greater heartwood area than some smaller trees. There was a tendency for some trees of low density to form more heartwood than so me trees of high density. Density was unrelated to growth traits but w as inversely related to fibre tangential and radial diameters. This im plies that phenotypic selection of trees on growth traits could result in trees of different density.