Growth and management of mixed Pinus sylvestris - Quercus robur stands in Flanders, Belgium

Abstract

Mature Scots pine (Pinus sylvestris L.) stands are dominating large parts of the Flemish forest area. Broadleaved species regenerate spontaneously under this pine canopy. This study studied the growth and development of two planted pine stands with an older natural regeneration, dominated by pedunculate oak (Quercus robur L.), and discussed management options for similar stands. The results indicated a rather good growth of the stands, with current annual increments of 5 m3.ha-1.yr-1. The pine overstorey is growing into valuable sawwood dimensions, while the broadleaved understorey slowly grows into the upperstorey. The quality of the regeneration is moderate but can be improved by silvicultural measurements (pruning, early selection). In both stands, an interesting (timber production, nature conservation) admixture of secondary tree species is present in the regeneration. Stand management is evolving from the classical clearcut system towards a combination of a type of selection and group selection system.