ohennus

Ohennus is a term used in Finnish horticulture and silviculture to describe the selective removal of shoots, buds, or small branches in order to reduce the density of a plant canopy. The practice aims to improve growing conditions for the remaining plant parts by increasing light penetration, air circulation, and resource availability, which can enhance growth, vigor, or fruit quality.

Etymology and usage

The word derives from the Finnish verb ohentaa, meaning to thin. In everyday usage, ohennus is distinguished from other forms of pruning by its focus on reducing density rather than shaping or removing large structural parts. It is applied in both gardens and managed forests, typically as a seasonal operation during periods of active growth.

Applications

In gardens and orchards, ohennus involves removing a portion of competing shoots or buds to balance canopy density and stimulate favorable branching patterns. It is used to improve sun exposure inside the canopy and to manage crop load indirectly by creating better conditions for the remaining growth. In forestry, ohennus refers to thinning operations that reduce stand density to promote the growth of selected trees, enhance wood quality, and influence stand structure and biodiversity.

Benefits and considerations

When performed appropriately, ohennus can boost vigor, increase fruit size and quality, and improve tree form in ornamentals and fruit crops. In forests, it can accelerate diameter growth of residual trees and improve resilience. Risks include over-thinning, which can lead to sunscald, drought stress, or loss of aesthetic or ecological value if not tailored to species and site conditions.

See also: pruning, thinning, silviculture, horticulture.