Groei en productie van populier in Nederland

Between 1947 and 2000, growth and yield of Poplar was studied in the Netherlands. To the permanent plots measured by Becking and De Dorschkamp/IBN, the permanent sample plots from HOSP were added, resulting in 235 plots and 1808 recordings.The development of the mean height hm with age t was found to be best described by a Chapman-Richards-model, with adjustment factors for dense stand and for different parameters for forest stands, line plantings, and for aspen, using site index h25. The diameter development up to a height of 7 m was best described with a Gompertz-model in t, hm and the initial spacing (SP0).The basal area increment IG was best explained by a power function in which hm, age, h25 and the Becking-Hart spacing index S% are included. For S% > 29.2 the basal area increment dropped with a non-linear function in S%. For dense spacing and for line plantings, other models fitted best.Combining all models, a stand projection model was constructed, which described the plot develop-ment as measured reasonably well.Yield tables were made for forests with different spacing, for forests with a wide stand with and with-out systematically thinning, for forest with very dense spacing including mortality, for line plantings without thinning, and for aspen with heavy thinning from below