Provenance Studies of Frost-resistant Eucalypts in South Africa

Provenance Variation ofEucalyptus nitenson the Eastern Transvaal Highveld in South Africa

“…Data from this trial indicate that NSW provenances grow better than VIC provenances on the ETH. Similar results were reported for a trial in Zimbabwe after 13,5 years (Quaile and Mullin, 1983), for a trial in South Africa after five years and eight years (Nixon and Hagedorn, 1983), and for one of the sites included in the present study after three years (Darrow, 1983). In contrast, VIC provenances grew better than NSW provenances in Australia after five years (Pederick, 1979).…”

“…In 1980, a trial composed of 12 provenances, many identical to the 1979 trial, was established on two sites on the ETH. Results from one of the sites included in this trial was reported at three years (Darrow, 1983). This paper compares and contrasts the growth of provenances at both sites at four years, examines provenance variation in the severity of Mycosphaerella leaf disease at one site, and discusses the interpretation of results in regard to selecting E. nitens provenances to be used for future planting and breeding in South Africa.…”

Growth potential ofEucalyptus globulussubsp.bicostataprovenances for the mid-altitude summer rainfall regions of South Africa

“…These areas are not suitable for optimum growth of E. grandis and are generally referred to as 'low productivity' sites. The mean annual temperatures (MATs) of less than 18 °C and altitudes above 1 050-1 300 m, depending on latitude, are not suited to the planting of E. grandis (Swain and Gardner 2003a), as this species displays extensive susceptibility to drought-and cold-induced mortality (Darrow 1983). These mid-altitude sites are also not suited to the growth of E. nitens provenances that usually perform well at altitudes greater than 1 350 m, but do not grow well on these lower-altitude sites.…”

The relative contributions of tree improvement and cultural practice toward productivity gains in Eucalyptus pulpwood stands

“…The genetic improvement of planting stock through selection breeding is recognised as a significant means of increasing yield per unit area (Namkoong et al, 1980(Namkoong et al, , 1988. Tree breeding strategies with eucalypts to increase yield or desirable traits such as stem straightness or wood properties, have been implemented with success in many parts of the world, including Portugal (Borralho et al, 1992), Chile (Arnold et al, 1991), Brazil (Campinhos and Ikemori, 1988), Morocco, Colombia, Spain and China (Eldridge et al, 1993),and South Africa (Darrow, 1984;Stanger, 1991;Denison and Kietzka, 1993). To maximise plantation production, systems that integrate both intensive silvicultural management practices and genetic improvement are required (Allen, 1998(Allen, , 2001.…”