Growth Response to Thinning in a Productive Eucalyptus globulus Plantation in Victoria, Australia
The production of high-value clear-wood sawlogs from Eucalyptus plantations requires early selection and pruning of the sawlog crop trees to produce knot-free wood and thinning to reduce competition and enhance growth rates. The trade-off in production of sawlogs and pulpwood was examined in two contrasting thinning treatments applied to a productive E. globulus plantation at Werribee, Victoria, Australia: Sawlog regime, Sawlog and Pulpwood regime. Higher density Pulpwood and Biomass regimes were used to measure potential site productivity. In the Sawlog and Sawlog and Pulpwood regimes, sawlog crop trees (220 trees·ha <-1>) were selected and pruned to 6m height at age 4 years. The plantation was irrigated with nutrient-rich wastewater during summer. Mean annual increment at age 11 years was about 33m<3>·ha<-1> in the Biomass regime. Standing volume in the Sawlog and Sawlog and Pulpwood regimes at age 11 years was approximately 41％ and 90％ respectively that in the Biomass regime. There was no difference in volume of the sawlog crop trees between the Sawlog and Sawlog and Pulpwood regimes, indicating that the dominant trees were not subject to significandy more competition in the stand at a density of about 600-700 trees·ha<-1> than at about 220 trees· ha<-1>. Following commercial thinning at age 11 years, growth of the sawlog trees in the Sawlog and Sawlog and Pulpwood regimes was similar. The results suggest that at least where water and nutrient supply are relatively abundant, E. globulus can be managed under a commercial thinning regime (in this study yielding over 100m <3>·ha<-1> pulpwood at age 11 years) without significantly compromising the growth of the sawlog crop trees.
David I Forrester Thomas G Baker
School of Forest and Ecosystem Science, The University of Melbourne, PO Box 137, Heidelberg, Victoria 3084, Australia Cooperative Research Center for Forestry
国际会议
The International Conference on Plantation Eucalyptus(桉树国际会议)
广东湛江
英文
30-37
2005-12-01（万方平台首次上网日期，不代表论文的发表时间）