A promising robotic harvester will resume limited trials in Washington this fall, and a few WA 64 trees near Prosser are ready.
“We are doing this because we are evaluating this variety as a potential variety for robotic tools, robotic harvest,” said Bernardita Sallato, Washington State University tree fruit extension specialist, at a field day on Sept. 24 at the Roza research farm near Prosser.
WA 64 is the latest apple from WSU’s breeding program. Nurseries are propagating the cultivar, to be marketed as Sunflare, while WSU maintains demonstration blocks comparing rootstocks and training systems at Roza and the Sunrise research orchard near Wenatchee.
In late September, Sallato and her team aggressively pruned a small section of a single row of WA 64 to expose fruit to the coming robot’s sensors and end effectors.
The robot is owned by CNH Industrial, which acquired the technology from advanced.farm, a California startup that seemed on the cusp of commercialization in Central Washington until closing shop in early 2025 due to lack of funding.
CNH engineers have retooled some aspects of the machine and want to privately test the tweaks at the Roza farm this season, Sallato said. The trial will not be open to the public, she said.
However, Sallato and her colleagues approached the orchard from the perspective that what’s good for the robot is also good for harvest efficiency overall, even with people.
“We are evaluating a lot of the horticulture aspects related to efficient mechanical harvest, and in my opinion, everything that we do, it will make our robot more efficient. It will also make our harvesting processes more efficient,” she said.
The tree fruit industry still has high hopes for an automated harvester and still funds research projects involving robots.
“We don’t want to quit on the robots,” said Dave Gleason, a horticulturist at Domex Superfresh Growers in Yakima, one of a few growers at the field day.
Engineers continue to improve the technology, he said.
The trade-off of pruning close to harvest is potentially robbing the fruit of carbohydrates and increasing the risk of sunburn. However, Gleason and Sallato both said that by late September, when WA 64 matures, trees have begun redirecting nutrients away from fruit and toward winter reserves, and the sun angle is not as dangerous as it would have been in August.
Sallato also discussed biennial bearing and thinning demonstrations. In limited observations, the cultivar will not self-thin like its cousin, WA 38, marketed as Cosmic Crisp. The WA 64 will require crop load management or risk biennial bearing.
The field day also visited an Allan Bros. Phase 3 commercial trial near Benton City.
The cultivar favors fruiting-wall tree architecture, said Manoella Mendoza, a project manager for the Washington Tree Fruit Research Commission, which oversees Phase 3 trials of the variety.
The other commercial trial is in a central-leader block near Quincy, where fruit maturity, coloring and sizing is inconsistent compared to Benton City, she said. •
