tyndning

Thinning, or tyndning in Scandinavian languages, is the practice of reducing the density of individual plants in a stand or population by removing a portion of the individuals. It is used in forestry, horticulture, and land management to relieve competition, improve growth, and guide stand development. Thinning is distinct from clear-cutting and from pruning, as it targets selective removal rather than wholesale harvest or structural modification.

In forestry, thinning aims to improve the growth and quality of the remaining trees, increase resilience to pests and weather, and influence stand structure and species composition. It is usually carried out after establishment and during stand development, when stocking is high. Common approaches are thinning from below (low thinning), which removes suppressed or small trees; thinning from above (crown thinning), which removes some trees to release light and space for others; and selective or free thinning, which targets specific trees for removal.

In horticulture and fruit production, thinning reduces fruit load or seeds to improve size, color, flavor, or harvest efficiency. Seedlings and young nursery stock may also be thinned to promote uniform growth and root establishment.

Effects of thinning include faster diameter growth of remaining trees, improved stem form and wood quality, greater understorey light, increased biodiversity in the stand, and altered competition dynamics. The timing and intensity depend on site conditions, species, management goals, and economic considerations. Thinning is typically part of sustainable forest management plans to balance timber yield with ecosystem health.