Pruning Technique in Young High Density Hedgerow Olive Orchards

In young high density hedgerow olive orchards tree canopies do not suffer of reciprocal shading and lack of light penetration. When canopies are small and trees are fast growing, high yield efficiency can be obtained. On the other hand, considering that canopy volume at maturity is constrained by the harvesting machine size and canopy shading, some growers try to slow down vegetative growth in order to delay problems due to excessive canopy growth. The aim of the present work was to determine if and, eventually, what kind of pruning has to be applied in young high density hedgerow orchards. In an 'Arbequina' high density hedgerow olive orchard planted in 2006, two different pruning techniques (removal of basal canopy (T1) and removal of basal canopy+hedging (T2)) were compared with non-pruning in 2009. Unpruned trees resulted more productive than T1 and T2 trees because of the removal of bearing shoots in T2 and T1. T2 increased shoot growth and stimulated vegetative growth. Canopy efficiency was larger in non-pruned trees, but harvesting efficiency resulted larger in pruned trees because of the removal of bearing shoots in portions of the canopy which were not harvested by the over-head harvester. Minimal pruning operations have to be applied in young high density hedgerow olive orchards. At this stage, pruning operations have to be limited to the removal of canopy portions not harvested by over-head harvesters.