High Pruning

High pruning represents the next developmental phase in high-value timber silviculture following formative pruning, typically initiated once a tree exceeds three meters in height and its stem diameter reaches fifteen centimetres.

Unlike natural self-pruning—which progresses too slowly in open or managed stands and leaves dead branch stubs trapped as internal defects—manual high pruning accelerates the clearing of the lower trunk to produce premium, knot-free wood outside a narrow core. Performed in a series of progressive lifts up to a maximum height of six metres, this intensive intervention restricts all future branch knots to a tight central cylinder, maximising the yield of pristine sawlog or veneer-grade timber.

To safeguard the tree’s health, foresters must strictly observe the 'rule of thumb,' removing branches before they exceed five centimetres in diameter and never stripping more than one-third of the live crown in a single lift to prevent growth stagnation. Cuts must be precisely executed outside the branch-bark ridge without causing flush cuts or leaving protruding stubs, allowing the vascular cambium to cleanly compartmentalise the wound.

While most broadleaves are pruned in late spring to encourage immediate healing, special exceptions apply based on specific tree biology; for example, walnuts must be pruned in mid-July (traditionally St. Swithin's Day) to prevent profuse bleeding of sap and subsequent physiological weakness. By focusing high pruning on a select cohort of high-potential crop trees per hectare, growers successfully convert standard forest trees into elite, high-value economic commodities.