| 摘要 |
Current practice has young trees planted in lines with gaps of around 4 m. This spacing is designed to allow access for machinery to the plantation for carrying out thinning and other work over the 50 year life of the forest. Successive thinnings are carried out at 12 to 15 year intervals result in approximately 300 stems per hectare after around 35 years and this remains stable for the last 15 years. According to this new procedure, the number of trees planted is doubled, by planting an extra row between the normal rows, i.e. planting at 2 m intervals. At the first thinning, after approximately 13 years, these intermediate rows are completely cleared, leaving the trees the normal 4 m apart. Further thinnings are then carried out in the conventional manner. These intermediate trees are thus extra yield from the same land area.
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