This spring, they're trying an alternate configuration that takes advantage of cherry trees' apical dominance by running two permanent scaffolds with fruiting uprights on wire.
"We're definitely learning as we go," Whiting says. "There won't be one system to fit all situations." Instead, growers will adjust the system to fit the vigor and precocity of their rootstock and scion combinations.
Cherries tend to grow upright branches rather than laterals, a plus with this architecture, Whiting says.
To produce fruiting walls, "We (now) want something in a scion that doesn't have a lot of lateral branching, which is directly opposite of what we've been looking for in the past," he says. "We're rethinking varieties we've discarded over time because they weren't grower-friendly."
Lapins, for example, have desirable upright growth habits, he says. Bings, too, perform well in fruiting walls. Third-year yields for Bings on Gisela 12 rootstock averaged 3 1/2 tons per acre, with 98 percent of the crop reaching sizes of at least 10 1/2 row.
The more open canopy improves light penetration, which should boost fruit sugar, Lang says. Reduced shade on fruit also may enhance firmness to some processing varieties such as Montmorency, which can suffer significant damage when shaken from trees during harvest.
Lang and Whiting say the changes to tree canopy also should provide better spray coverage.
"The older systems require more material and water to blast through multiple layers of canopy," Whiting says. With fruiting walls, growers don't have that vegetative density.
That provides potential for targeted sprayers and visioning systems for more advanced harvest and pest or disease control technology, he says.
Another technical innovation could be over-row systems that spray downward for better penetration and reduced drift, Whiting says.
The expense of establishing new orchards that incorporate the system may be the biggest drawback, he says. But the precocity and yields alone soon pay for the investment—even without considering labor savings.
And, Harris says, the choice soon will come down to investing the money in new orchards or shutting down altogether because of labor shortages and increasing labor costs.
Economic factors have drawn Morgan Rowe, owner of Rowe Farms in Naches, into joining Whiting's research this year with a newly planted test block of Selah cherries on three different rootstocks.