Stand height response following variable spacing of wheat field white cypress pine regeneration in New South Wales [Callitris glaucophylla]
1990
Horne, R. (New South Wales Forestry Commission (Australia). Wood Technology and Forest Research Div.)
Four field experiments investigated the stand height response of an area of 1952-56 wheatfield regrowth to a variety of stocking reductions, applied in the first 14 y after germination. Stand height responses of the tallest 250 trees per ha were calculated for a range of spacing treatments to determine the degree of early release necessary to optimise stand height growth. At 14 years, a range of manually applied spacing treatments were established in the regrowth, such that some treatment plots overlaid earlier treatments, limiting the extent of growth comparisons. However, it is shown that the optimal spacing treatment of the later treatments was 4.9 m x 4.9 m and that cypress pine regeneration retained an ability to respond markedly to a delayed release from a "locked" condition. After 32 years, the tallest stands were those that had been manually thinned most frequently.
显示更多 [+] 显示较少 [-]