Data used as an indicator of mechanical olive harvest season

When and how harvest olives are among the most important issues to improve quality and quantity to ensure the best net return to growers. Trunk shakers are commonly used in mechanical harvesting to detach olives. Field trials showed that with this equipment less than 100% of the production is detached, usually 70% to 90% (Michelakis, 2002). It is important to increase the percentage of fruits harvested, to reduce losses. To achieve this goal factors affecting mechanical olive harvesting must be known, to be used in the definition of harvest season. Some of these factors are the result of the orchard management, like tree shape, canopy density, pruning methods. Others depend on the cultivar, such as fruit removal force (FRF), fruit weight (P) and the ratio between them. FRF and P are considered decisive in the detachment process. Results of field trials carried out in the Northeast of Portugal with "Cobrancosa Transmontana" cultivar show the FRF, P and their ratio evolution in the ripening period. They have potential to become indicators of the mechanical olive harvest season. (C) 2015 Published by Elsevier B.V.