Canopy management in super high-density olive orchards: Relationship between canopy light penetration, canopy size and productivity

In super-high density olive orchards, canopy size is constrained by the size of the harvesting machine and canopy efficiency is limited by reciprocal tree shading. Thus, correct management of light distribution within the tree canopy and the use of large canopy volumes are essential means for obtaining large orchard yield. We conducted experiments on 'Arbequina' and 'Maurino' olive trees trained in super-high density olive orchards to assess the effect of pruning strategy on light distribution, shoot and tree productivity and to determine how to optimize canopy management for high tree productivity and mechanical harvesting. Shoot flowering was closely related to light exposure during the previous summer and to shoot length. On this basis a pruning technique based on the yearly thinning of branches (selective pruning) was evaluated to reduce canopy density and improve light distribution and at the same time increase canopy volume (with flexible branches compatible with overhead harvesting machines). The new selective pruning strategy improved light distribution, increased canopy size and improved yield compared to mechanical topping, which is currently the most common pruning system in high density olives.