A mechanical olive harvester prototype consisting of a 2m high by Im diameter cylinder with 370 stacked radiating Im fiberglass rods with a horizontal whipping motion created by a top counterweight rotating at 500 I-pm was evaluated for two seasons, 1996 and 1997, on hedged trees. Percentages of olives removed from previously tagged branches was the method used to evaluate harvester efficiency. Significantly better fruit removal efficiency, average 91%, was achieved with the most accessible tagged branches, those 1/4th and 3/4th of the way from the leading edge of the tree canopy as the harvester approached, than from branches on the leading edge, 56%, and trailing edge, 65%, of the canopy. Cull rates for damage ranged from 1-3.1% higher than hand harvested olives. Leaf loss was negligible. Hedging done in May, 1996 did not significantly decrease yield or crop value in the year of pruning or the subsequent year. Topping significantly decreased both yield and value the year of pruning, but not the subsequent year. Results thus far suggest this harvester can efficiently harvest olives but the trees will need to be hedged to a triangular shape no lower than Im from the ground. The tines of the harvester must connect with the branches to remove the olives. Further engineering development, including a fruit retrieval system, is required for final usable units.
