Tuyển tập các báo cáo nghiên cứu về lâm nghiệp được đăng trên tạp chí lâm nghiệp quốc tế đề tài: "Discussion about the articles by E Lahde et al in Ann Sci For (1994) 51, 97-120: "Structure and yield of all-sized and even-sized conifer-dominated stands on fertile sites" and "Structure and yield of all-sized and even-sized Scots pine-dominated stands" Pierre. | 667 Ann Scì For 1995 52 667-673 Elsevier INRA Discussion Discussion about the articles by E Lahde et al in Ann Sci For 1994 51 97-120 Structure and yield of all-sized and even-sized conifer-dominated stands on fertile sites and Structure and yield of all-sized and even-sized Scots pine-dominated stands by Pierre Duplat Office national des forets departement des recherches techniques 77306 Fontainebleau France I have some reservations about 2 papers by E Lahde et al in Annales des Sciences Forestieres 1994 51 97-120 entitled Structure and yield of all-sized and evensized conifer-dominated stands on fertile sites and Structure and yield of all-sized and even-sized Scots pine-dominated stands . I will express the most important ones referring to the first paper the second one using the same methodology. INTRODUCTION The material used comes from the third national forest inventory 1951-1953 in southwestern Finland on Myrtillustype sites or more fertile ones temporary plots 1 000 m2 in size inventory by species and diameter class starting from the 2-6 cm class measure of dominant height 100 largest trees ha and estimation of current volume increment over the 5 preceding years by boring every tree . Each plot is considered as a stand with its inventory its total stem volume tariff function s its dominant height and its total stem current increment. Precise criterions applied to the allspecies diameter histogram of each stand make it possible to decide whether it belongs to 1 or the other of 2 groups of structure all-sized and even-sized 83 of the stands may thus be classified in 1 or the other group and constitute the material for the study. The stands belonging to each large group of structure are classified into 2 groups of composition depending on whether they include less or more than 120 broad-leaved trees per hectare coniferous mixed . The yield of each group structure X composition is judged on the basis of 2 results - the mean of current increments for stands .