That’s a source of some frustration for Louise Ferguson, a University of California Extension specialist who has spearheaded much of the research on mechanization. In an interview, she pointed to successes in research that showed limited canopy or trunk damage and production of fruit that passed muster in taste tests.

“It’s a source of frustration to be so close,” Ferguson said, “but the average olive grower doesn’t want to budge.”

Because most olive growers have diversified operations, she said, they may not know “what part of the operation is eroding their capital. Hand-harvesting costs are driving this industry into the ground.”

Ferguson said the industry’s attention to thwarting the olive fruit fly diverted some of their attention and resources away from coming up with “turnkey machines” that could be used for harvesting in the orchards.

She’s convinced that it will be necessary for growers to “change the trees and the machinery at the same time,” to use pruning and shaping of trees along with the machinery that shakes olives from the trees.

Ferguson also believes mechanical pruning can be used to help address the issue of alternate bearing in olives.

The Exeter meeting opened with Elizabeth Fichtner, UC Extension specialist on olives for Tulare County, talking about research aimed at better understanding alternate bearing in olives.

Fichtner and Carol Lovatt, professor of plant physiology at UC Riverside, are doing a research project that looks at the effect of shoot growth and whether use of plant growth regulators could address the alternate bearing issue.

“Alternate bearing makes it hard to manage budgets,” Fichtner said.

She said the problem may be exacerbated by lack of harvesting in an off-year when growers simply leave olives on the trees because there are so few and picking is costly.

The study also looks at what has been done to mitigate alternate bearing in citrus and avocado and to see if that may work in olives.