December 1, 1997
- mechanical harvesting
The field performances of four machines were evaluated for mechanical removal of oranges from the tree during the 1995-96 season. After 5 to 20 sec of shaking per tree, Compton trunk shakers removed 67 to 98% of the fruit and Orchard and Grove Machinery trunk shakers removed 63 to 96% of the fruit. Trunk diameters ranged from 5 to 11 inches. Fruit removal was directly related to shaker head displacements which varied from 1 to 2 inches. A canopy shaker with 2 nylonspoked drums oscillating at 3.5 inches displacements removed 70 to 90% of the fruit in the canopy volume penetrated by the spokes and 52 to 70% between the outer canopy and the trunkline or tree center. Fruit removal generally decreased with increasing ground speed from 1 to 2 mph. The fourth unit was the Crunkelton machine which had a rectangular array of 7 ft long tubes with spring loaded fingers which were inserted and withdrawn from the tree canopy. Within the canopy volume penetrated by the tubes, 67 to 77% of the fruit was removed after 1 insertion and 73 to 91% was removed after 2 insertions.