Continuous harvesting of olive orchards with wide canopies in hedge

Abstract

Super high density (SHD) olive groves with rows trimmed in hedge are very common. Self-propelled over the row equipment is used for harvesting. However frequent trimming of the trees is required to adequate the volume of the canopy to the limited dimensions of the harvester. The cost associated with the trimming operation and the limitation on tree growth, reflected in limited olive yields per tree will have a negative influence in the overall production costs. Moreover, worldwide, there is only a small number of olive varieties suited to SHD olive groves, restricting greatly the number of brand olive oils. An alternative is to perform less frequent trimming actions, leaving trees with a wider canopy and harvest with a side row continuous harvester being developed in the University of Évora. The side row continuous harvester comprises two symmetrical harvesters that follow a tree row one at each side. Each harvester is a trailed type structure towed by a farm tractor which also drives the harvest hydraulic power pack. A second operator controls the harvest through electro-hydraulic controls. A vibratory mast with flexible rods detaches fruits which are collected at a catching platform. Fruits are conveyed to a temporary storage bag which is hydraulically lowered to the ground when full. The row side of the harvester is bordered along the edge by a line of collapsible synthetic scales to avoid tree trunk damage. Preliminary field trials were done in an olive grove located in the Alentejo region of southern Portugal, of the Portuguese olive variety ‘Galega’, with 7 years of age, installed in the array of 6m x 2.5m. This orchard is privately owned and reveals high crop management. The canopies of some tree rows were left to grow wider to be compared with rows normally trimmed for the over the row harvester owned by the farmer. This paper describes one year of preliminary testing the wider canopy alternative in comparison with the common practice of olive grower, describing briefly the technology used for harvesting, and presenting the major results in terms of olive yield, olive detachment efficiency, harvesting cost and difference of market value of olive production and harvest cost.