Groei en productie van gewone esdoorn in Nederland

In the Netherlands growth and yield research on sycamore was done from 1976 to 2001. This includes studies by the Dorschkamp/IBN research institute and by Wageningen University. To-gether with the permanent sample plots from the timber prognosis system HOSP, this comprises a dataset of 32 plots with 113 recordings. For the development of top height htop with age t Cieszewski’s polymorphic model with site index h50 and three additional parameters fitted best.The diameter development up to stand height of 7 m was described with a model of Jansen et al., a power function in htop and initial spacing (N0). From a stand height of 7 m upwards, the basal area in-crement (iG) was described by Jansen’s et al. model based on a power function with htop, t, year of re-cording (yor), and the stand density of Hart (S %). For S% > 16.3 the basal area increment decreases non-linearly with increasing %. The model contains a correction factor for yor, although this was not significant, as the year of recording (yor), turned out to be not significant. The effect of thinning on the diameter after thinning was modelled with the La Bastide-Faber model.The models were used to construct a yield table with five site classes and one thinning intensity.