Wood and fibre productivity potential of promising new eucalypt species for coastal Zululand, South Africa

Summary

In South Africa pressure is increasing to improve the quantity and quality of eucalypt wood being produced from the existing forestry land base, and to identify species that would enable profitable forestry on land currently considered marginal. In a series of site x species interaction trials established on the Zululand coastal plain during 1992, alternative eucalypt species were compared with a number of commercial eucalypt species and clones at three sites. At rotation age of 7 y, the wood and fibre productivity of the five most promising new species, namely Corymbia henryi, C. citriodora ssp. citriodora. Eucalyptus longirostrata, E. pilularis and E. tereticornis, was assessed at two of the sites.

On the basis of merchantable wood production, E. longirostrata Monto provenance showed excellent potential for high productivity (wet) sites on the Zululand coastal plain, and C. citriodora ssp. citriodora and C. henryi excellent potential for marginal (moderately dry) sites. On the basis of fibre production, E. longirostrata Monto and C. henryi showed excellent potential for high productivity sites, and C. citriodora ssp. citriodora and C. henryi excellent potential for marginal sites.

Eucalyptus longirostrata could be a good partner for E. grandis and E. urophylla for the production of hybrids better adapted to the range of environmental conditions in coastal Zululand than either of the latter two species. In such hybrid combinations, the high basic wood density of E. longirostrata could be of advantage to the local hardwood woodchip export industry.

Keywords:

• plantations
• adaptation
• species trials
• site-species matching
• productivity
• wood properties
• pulping
• Eucalyptus
• Corymbia
• South Africa