Li B.,Hunan Forest Botanic Garden |
Arnold R.J.,Chinese Academy of Forestry |
Arnold R.J.,University of Melbourne |
Luo J.,Chinese Academy of Forestry |
And 2 more authors.
Australian Forestry | Year: 2016
There is a long history of eucalypt planting in inland regions of southern China where humid summers and frequent winter frosts and extreme cold events are features of the climate. Although early eucalypt plantings suffered widespread failures, some species managed to survive with individual trees in some plantings growing to impressive sizes with diameter at breast height (DBH) exceeding 50 cm. One of the most productive and best adapted species in the plantings was Eucalyptus camaldulensis. Two species-provenance trials were established in southern and central Hunan province in 2006 primarily to explore the potential of E. camaldulensis and the related E. tereticornis, but also to provide comparisons with two other species with potential for the climate. The trials included 65 provenances representing six taxa from four species: E. camaldulensis, E. tereticornis, E. amplifolia and E. macarthurii. Three provenances represented improved seed sources from Africa, whilst the others were natural stand provenances. Eucalyptus amplifolia var. amplifolia demonstrated the best potential for growth and survival up to age 5 years. Eucalyptus macarthurii had the best cold tolerance, but relatively poor performance for growth and survival. Both E. tereticornis and E. camaldulensis demonstrated reasonable cold tolerance, but growth and survival of E. camaldulensis var. camaldulensis provenances from temperate to subtropical climatic areas with dry summers and winter-dominant rainfall (Köppen climate classification Csa) were markedly inferior than those of E. tereticornis ig. tereticamal and E. tereticornis ssp. tereticornis sourced from tropical and subtropical environments with summer-dominant rainfall (Köppen climate classifications Aw and Am). Seedlots of E. camaldulensis, E. tereticornis and E. macarthurii from improvement programs in Zimbabwe and South Africa mostly proved inferior to or no better than the best natural stand provenances of the same species in the Hunan environment. © 2016 Institute of Foresters of Australia (IFA). Source
Arnold R.,China Eucalypt Research Center |
Arnold R.,University of Melbourne |
Li B.,Hunan Forest Botanic Garden |
Luo J.,China Eucalypt Research Center |
And 3 more authors.
Australian Forestry | Year: 2015
Inland humid subtropical regions of China’s southern provinces have substantial areas of land potentially available for forest plantation development. Such development would help address a substantial deficit in domestic production compared with demand for timber and fibre raw materials. However, the tropical and subtropical eucalypt varieties that are the basis of highly productive and commercially successful plantations in China’s warmer coastal regions have proved poorly adapted to inland regions which are characterised by hot humid summers and frequent winter frosts and cold events with temperatures down to –8°C or lower. To evaluate a range of Eucalyptus species and provenances for plantation development in this subtropical environment, three species–provenance trials were established in southern and central Hunan province from 2001 to 2004. Included in these trials were 64 provenance seedlots representing 22 species and a locally selected Eucalyptus camaldulensis clone. Five of these seedlots represented somewhat improved sources from South Africa, whilst the others were unimproved natural stand provenances. Species that demonstrated the best growth and survival at age 6 years were E. amplifolia var. amplifolia, E. benthamii, E. dunnii and E. dorrigoensis. Species which showed reasonable performance in at least one trial and warrant further investigation include E. saligna × E. botryoides and E. deanei. Whilst E. macarthurii had the best cold tolerance, it had relatively poor performance for growth and survival. Provenances from imported improved sources (from South Africa) in most cases proved inferior to, or no better than, the best natural-stand provenances of the same species, providing salutary guidance for prospective growers. © 2015 Institute of Foresters of Australia (IFA) Source