Holding promise to reduce labor needs, a four-year research project may bring the production, harvest and marketing of stem-free cherries closer to commercial viability for Northwest growers.

Matthew Whiting, Prosser, Wash.-based associate professor and extension specialist for tree fruit physiology for Washington State University, said the U.S. Department of Agriculture-funded project has explored the total market approach to mechanically assisted harvest technology.

Researchers, now in the project’s fourth year, have explored all aspects of mechanically assisted harvesting, he said, from orchard design to consumer acceptance of stem-free cherries.

There is an effort by researchers to lay out the whole system, he said, so growers who are interested in pursuing the technology can do so with confidence.

That how-to approach will advise growers on everything from preferred varieties, planting and pruning guidance, assisted harvesting approaches and handling of fruit, and insight on retail acceptance, he said.

Whiting said the research is nearly done.

The handling, packaging and marketing parts of the research project are in place, but he said more work remains on the actual harvest technology.

“We’re focusing now on shake-and-catch technologies rather than the full machine harvest,” he said. “It really comes down to more from the engineering elements.

Stem-free appeal

If growers feel that finding labor for harvest will be a worsening problem in future years, they may be interested in designing their orchards so they can utilized mechanically assisted harvest technology, he said.

Researchers have employed the upright fruiting offshoots design for cherry orchards used with the system, Whiting said. It is a high-density, high-efficiency, two-dimensional design, Whiting said.

“How you train the trees makes a big difference in how you efficient the harvest technologies will be,” he said.

Some growers are beginning to plant orchards according to the upright fruiting offshoots design, he said.

Whiting has talked said stem-free cherries can work with current orchards and especially with orchards designed according to upright fruiting offshoots system.

“There is little to no resistance at the retail level, from the consumer’s point of view, to buying cherries without stems,” he said

More cultivars, genetic tests

Longer-term objectives for researchers include the development of a full season of sweet cherry cultivars that are well suited for mechanical harvesting and boast high consumer appeal.

Genetic researchers on the team are looking for an effective genetic test that could be used to screen seedlings and determine which are most suited for mechanical harvesting.

Whiting said the research project will look for funding from other avenues in the years ahead.

“We would like to move a couple of the technologies to commercialization,” he said. “We’re not quite to being able to do that,” he said.

In that regard, he said the equipment likely to be commercialized would be the shake and catch harvesting system.