Optimization of chestnut production within a sustainable development frame.
Résumé
Diversilication of agro-ecosystenis can play a role in developing sustainable agriculture insofar as they allow for the diversification of products and goods on the same farm. The present study deals with the possibilities of 'fruit and wood' orchard management in the case of chestnut trees. The main objective of this work is to determine, for two clones of hybrid trees Castanea sativa x Castanea crenata, the technical methods for getting (from the same tree)nuts in the short term and quality timber in the long term. Four varying lengths of pruned stems were tested on trees between three and eight years of age in a trial located in southwest France. After five years of pruning, growth was reduced by 3 to 4 % in height and by 13 to 23 % in diameter, according to fruit pruning literature, but for the two lengthiest pruning types of the more vigorous clone, the pruning effect is positive, indicating fast top growth reaction to pruning of branches, assesse to be about + 6%. For fruit production, the reduction due to pruning is only in terms of bur number and varies from 30 to 70% between fruit pruning and forest pruning. The maximum lenght prunable in chestnut is limited by the amountt of natural defects, but it can reach a maximum of 7 m.