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IVES 9 IVES Conference Series 9 Cultures des vignobles en forte pente: possibilités de mécanisation. Effet de l’exposition et de l’orientation des rangs

Cultures des vignobles en forte pente: possibilités de mécanisation. Effet de l’exposition et de l’orientation des rangs

Abstract

Plus de la moitié du vignoble suisse (14’000 ha) est situé sur des coteaux en forte pente (> 30%). Dans certains vignobles, la pente naturelle du terrain a été réduite par la construction de terrasses soutenues par des murs. Ces murs, établis depuis des générations, constituent souvent une valeur paysagère de haut niveau. Dans ces situations, la culture de la vigne s’est généralement faite dans le sens de la pente, où une multitude de ceps (> 10’000 ceps/ha) conduits en gobelet sur échalas tirent le meilleur profit du rayonnement lumineux. Ce système de conduite limite fortement les possibilités de mécanisation et exige de ce fait un nombre élevé d’heures de main-d’œuvre par an. Pendant de nombreuses années, les façons culturales ont été faites au moyen d’outils tirés par un câble, entraîné par un treuil. Cette mécanisation est pratiquement abandonnée aujourd’hui, l’entretien des sols se faisant essentiellement par désherbage chimique. Cette pratique, liée à la diminution des apports de matière organique, a contribué à augmenter la sensibilité des sols à l’érosion, en particulier dans les terrains peu perméables.
La réduction des risques d’érosion et la nécessité de diminuer fortement les coûts de production ont exigé une transformation complète de la culture des vignobles en pente. Dans les situations où l’utilisation du tracteur interligne était possible (pente inférieure à 35%, grandeur des parcelles et possibilités d’accès suffisantes), le système de conduite mi-large (150 à 200 cm d’interligne), avec des rangs à un seul plan de palissage orienté dans le sens de la pente, s’est fortement développé. Les possibilités de mécanisation sont proches de celles des vignobles de plaine. Une gestion du sol, adaptée à la nature du terrain, doit y être appliquée pour réduire au maximum les dégâts d’érosion. L’enherbement des sols constitue une technique idéale lorsque les disponibilités en eau sont suffisantes.
Dans les situations où l’emploi du tracteur, dans le sens de la pente, n’était pas possible (déclivité supérieure à 35%, forme des parcelles inadaptée), la rationalisation s’est faite en orientant les rangs en travers de la pente et en cultivant la vigne en banquettes, selon les courbes de niveau. Cette technique, traditionnellement utilisée dans le vignoble du Tessin pour réduire les risques d’érosion et d’éboulement dus à la forte pluviométrie, inégalement répartie avec souvent des orages violents, s’est largement répandue dans les vignobles de suisse alémanique et française. La culture en banquettes garantit une bonne protection du sol contre l’érosion, augmente sensiblement les possibilités de mécanisation des vignobles en forte pente et diminue la pénibilité du travail manuel (Murisier, 1981; Murisier et al., 1984; Murisier et Ferretti, 1999).

DOI:

Publication date: February 24, 2022

Issue: Terroir 2000

Type: Article

Authors

F. MURISIER, M. FERRETTI, V. ZUFFEREY

Station fédérale de recherches en production végétale
de Changins, Centre viticole du Caudoz, CH-1009 PULLY

Tags

IVES Conference Series | Terroir 2000

Citation

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