Do old wild service tree (Sorbus torminalis [L.] Crantz) respond to competition release?

摘要

This study addresses the question regarding the extent that wild service tree (Sorbus torminalis) is able to respond to reduced inter- and intraspecific competition by thinnings even at ages above 80 to 100 years. We compared two samples, which have been subjected to different treatments. Whereas the first sample, 32 trees randomly distributed within a 3 ha stand, was favoured by a heavy thinning in 2000, the second sample of the same size and located in an adjacent forest reserve, remained untreated. Yearly measurements of diameter growth and two inventories of all competitors were carried out. The results indicated that even old wild service trees respond to thinnings by an immediate increase in diameter growth. The study confirms the high sensitivity of wild service tree to competition. This is the reason why early and repeated thinnings in favour of vital trees of that species are recommended. The results of this study however show that even quite old trees can substantially be supported by silvicultural interventions aiming at keeping this species alive and producing for reasons of biodiversity and/or wood production.