Influence de la fertilisation minérale sur la fructification du Hêtre ( Fagus silvatica )

Abstract

A fertilization experiment in the West of France (Fougères) and another one in the East of France (Darney) showed a considerable effect of fertilization on the fructification of beech. In Fougères the number of male flowers was 70 p. 100 greater in fertilized plots, than in non fertilized plots, the female flowering was increased 2.7 times by fertilization. The percentage of sound beech nuts is also higher after fertilization. Those different effects increase jointly the number of sound beech nuts for about 3.4 times in Fougères and 3.38 times in Darney. The effect of fertilization seems to be due to the application of nitrogen and to a certain extend also of phosphor. A NP fertilization can therefore be recommended. Increased fructification was obtained even in stands of high yield (Darney) and also in older stands (140 years, Fougères). The fertilization effect seems to be independent of the types of humus: fructification is increased as well on sites with raw humus (mor), moder and acid mull. In Draney the effect was obtained even three years after the application of the fertilizers. Some questions have still to be answered: - the duration of the effect of a unique application of a fertilizer, - the effect on sites with mesotrophic, autrophic mull and calcareous mull.