More than half of New Zealand's Radiata forests are pruned three times in the first 10 years of life. This unique but labour intensive approach produces the highly prized, knot-free, Clearwood.
Pruning regimes vary but, in general, the first prune or "lift" is done when trees are 5~6m high. There are two more prunings before the trees reach 8m - always leaving 3~4m of photosynthesising crown.
Trees grow upwards and outwards. If a nail is hammered in 5m up the tree, it will remain at that height from the ground. But it will be progressively covered by new wood as the tree lay down more rungs with each season.
The same applies to pruned branch stubs - they stay at the same height and clearwood covers them as the tree grows. The bark will retain the pattern of "whirls" from where the branches were pruned, but don't be deceived: there is excellent clearwood directly below.
The defect "core" in the centre of the pruned is narrow and well covered with high-value clearwood.