Achievements in forest tree genetic improvement in Australia and New Zealand 3: Tree improvement of Eucalyptus dunnii Maiden

Summary

Eucalyptus dunnii Maiden has been widely planted in subtropical Australia, with a total of almost 39 000 ha established in commercial plantations in northern NSW and southern Queensland. Internationally, it has become recognised as a premium pulpwood species and its sawing properties have been considered superior to those of Eucalyptus grandis. Forests NSW established a pedigreed tree improvement program for E. dunnii in 1995, and this is the most advanced program for this species in Australia. The main breeding population has been characterised for both pulpwood and sawlog traits, and improving the timber's dimensional stability during drying has been identified as a priority of the program. As clonal propagation of E. dunnii by cuttings is not an economic means to deploy improved germplasm into commercial plantations, Forests NSW has established three clonal seed orchards for solid wood and pulp end uses, and plans to establish a fourth in 2007. A range of E. dunnii hybrids with high-value timber species has been produced with the aim of improving the wood properties of the species.

Keywords:

• breeding programs
• hybrids
• wood properties
• shrinkage
• dimensional stability
• pulpwood
• propagation
• Eucalyptus dunnii