Chemical induction of fruit abscission in olives

To facilitate mechanical harvesting of olives by trunk or limb shakers, and increase fruit removal, research has continued toward reducing the fruit-stem attachment force. Previous studies in California have shown that ascorbic or iodoacetic acid are effective in reducing the attachment force of olive fruit, but only when applied under conditions of very high air moisture. Attempts at artificially increasing the humidity surrounding the trees during or following spray application have been unsuccessful. The addition of surfactants or penetrante has not enabled use of ascorbic or iodoacetic acid to effectively loosen olive fruits under the low humidity conditions which prevail during the table olive harvest season in California.