Tuyển tập các báo cáo nghiên cứu về lâm nghiệp được đăng trên tạp chí lâm nghiệp quốc tế, đề tài: " Sessile oak seedling fertilization and leaf mineral composition in western France. | Ann Sci For 1996 53 605-613 Elsevier INRA 605 Original article Sessile oak seedling fertilization and leaf mineral composition in western France M Bonneau Departement des recherches forestieres Centre Inra de Nancy 54280 Champenoux France Received 6 September 1994 accepted 31 October 1995 Summary Three experiments were conducted in the Foret de Blois in western France on leached chemically poor soils with limited water drainage stagnic luvisols in the FAO classification in young 2-10-year-old sessile oak seedlings from natural regeneration. The main limiting factors for growth were phosphorus and nitrogen. In the better soils P2O5 in the A horizon extracted by H2SO4 extraction followed by OHNa extraction according to the Duchaufour method PKCa fertilization was not efficient and addition of N was necessary to improve height and diameter growth. In the poorest soils 1-P2O5 in the A horizon PKCa fertilization without N enabled a 40 gain in height and a complete NPKCa fertilization enabled a 100 gain during at least 5 years. Optimum composition for leaves sampled in August and ratios between elements were estimated as N 23 P K Ca 9 N P 15 N K K P . fertilization leaf mineral composition natural seedlings Quercus petraea I leached soils with pseudogley Resume Essais de fertilisation et composition foliaire de chênes sessiles dans I ouest de la France. Trois essais de fertilisation ont été effectues en foret de Blois dans I ouest de la France sur des sols lessivés à pseudogley luvisols stagniques de la classification FAO sur de jeunes 2 à 10 ans semis de chêne sessile Quercus petraea Issus de regeneration naturelle. Le phosphore et I azote sont les deux principaux elements limitants pour la croissance en hauteur et en diamètre. Dans les meilleurs sols 0 09 1 de P2O5 dans I horizon A J extrait par une extraction à H2SO4 suivie d une extraction à OHNa selon la methode Duchaufour une fertilisation PKCa n