Introduction Eucalyptus grandis is the most widely planted hardwood in South Africa, accounting for about 23% of the total plantation area of 1.4 million ha (DWAF 2004). The harvested tree stumps of E. grandis coppice to form second and more crops, which are normally harvested at 7-10 y of age (The South African Forest Owners Association 1997). In South Africa, this species is grown predominantly for pulpwood and mining timber. Productivity from these plantations is relatively high and ranges from about 17 to 52 [m.sup.3] [ha.sup.-1] [y.sup.-1]. The high growth rates and success of this species can be attributed to the deployment of high quality genetic material, combined with intensive silvicultural management regarding site preparation (Smith 2000), correct site-species matching (Schonau and Purnell 1987), optimum planting density (Coetzee 1991), appropriate vegetation control (Little and Gous 2000) and adequate nutrition (Schonau 1983; Herbert and Schonau 1989).