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Concerns about high labor costs and possible labor shortages in the future have encouraged researchers to design and test new labor saving automated tools and machinery for use in tree fruit production. Labor is the largest single production input. Depending on the production system and technology used, it takes approximately 130 to 210 man-hours to grow an acre of apples or pears annually. Cherries are even more labor intensive, ranging from 300 to 400 hours per acre. Labor is approximately 35 to 50% of the cost of producing an apple or pear, and closer to 70% of the cost of producing cherries. (Source: D. Brown, WSU Extension Today, 2007)

According to Gallardo and Brady (2014), “The number of migrant workers is forecasted to decrease by 1% per year in the next five years, and an estimated 12% of orchard acres on farms are in the financial position to consider mechanization.” See the report here.

Dr. Jim McFerson, Manager, Washington Tree Fruit Research commission noted that he sees “being able to pick a crop in a timely fashion as one of the greatest production challenges that the tree fruit industry faces.” Growers are facing a shortage of workers and having a difficult time obtaining workers through the H-2A guest worker program according to Brent Milne of McDougall and Sons in Wenatchee. He says growers need more efficiency using available personnel, and that is the goal of automation. See “Labor worries spur automation,” G. Warner, Good Fruit Grower, 2014.

There are a number of automated labor saving devices being developed and tested today to reduce labor costs or improve efficiencies so that farm personnel can more rapidly complete orchard tasks. Some of the innovative technologies being employed in tree fruit production are for: pruning, thinning, irrigation, pest and disease control, harvest and more.

In the USDA Specialty Crop Research Initiative project “Comprehensive Automation for Specialty Crops (CASC)” led by Carnegie Mellon University, scientists from Washington State and other universities, agricultural machinery companies and the USDA-ARS focused “to develop comprehensive automation strategies and technologies for the specialty crop industry, with an initial focus on apples and nursery trees.” In this project, the key research themes included: autonomous orchard vehicles, harvest assist systems, precision pest management, tree caliper and counter and crop yield estimation. See the CASC Project Portfolio for a comprehensive project update (pdf file, 58 MB).

Barriers to Adopting New Technology

There are challenges with adopting new technologies to mechanize and automate orchard operations. Many growers prefer the “tried and true” methods that have worked in the past. Change is often difficult, and learning new ways of doing things takes time. Orchard workers also need to adjust to new technology, as they have learned to be highly efficient at their work, and are able to handle fruit carefully, with “the human touch.” Automated equipment is expensive and growers want to know if the expense will be worth the investment for future savings or increased efficiencies. Smaller acreage orchardists need affordable, smaller-scale equipment for their farms.

Many orchards are not organized in ways that would accommodate the use of some new automated technology. For example, some tree fruit operations are located on hilly and terraced sites, and the lack of uniformity make these sites unsuitable for some equipment. The safe use of platforms depends on the site topography, slope and orchard planting systems in place. According to a WSU research survey of Washington growers in 2010, growers indicated that they may choose not to purchase platforms for the following reasons: 1. high cost, 2. orchard structure that would be incompatible to automation, and 3. steep and uneven terrain. See Economic analysis of technology adoption by Washington apple growers (Taylor and Gallardo, 2011).

Making automation a reality in tree fruit orchards can be a challenge because no two orchards, systems, or growers are alike. Autonomous equipment is usually well suited for the newer high-density blocks with narrow, uniform, basically two-dimensional fruiting walls. In such orchards, equipment can easily move down the rows allowing workers access to structured fruiting walls on either side. Platforms, driverless vehicles, and mechanical thinners and pruners may be feasible for growers to use in these types of systems. Moving ladders from tree to tree for thinning fruit (for example) and using poles to hand place insect traps is very time consuming and inefficient. Finding the right equipment that significantly enhances efficiency is critical. See two related videos: Autonomous orchard vehicle page, CASC website.

Modern Technology

The WSU news article “Orchards of the future-Think Automation,” featured research that WSU-CPAAS was working on in collaboration with the University of California and others, on a USDA project “Precision canopy and water management of specialty crops through sensor-based decision making” to bring new technology to specialty crop growers. See the project website here.

In orchards of the future, sensors to measure sunlight absorbed by trees, driverless vehicles patrolling orchards for insect pests, vehicles taking 3D images of fruit development and orchard managers being updated with data sent directly to their smartphone is becoming a practical reality. Dr. Qin Zhang, director of WSU’s Center for Precision and Automated Agricultural Systems (CPAAS) noted “Our research is aimed at developing and integrating soil- and plant-based sensors to optimize management in orchards and vineyards.” Automation research will help achieve excellent fruit quality and provide growers with ways to work with labor cost challenges and shortages and improve efficiencies. Source: CAHNRS reconnect, B. Clark, December 2012 See the article here.

Although there currently are driverless orchard vehicles, sensors collecting environmental data that is sent to growers in real-time, automatic insect traps catching, identifying and counting insect pests, etc., most orchard field automation still requires humans and machines working together. Humans are still the most effective apple pickers, because they are quick, efficient and gentle on the fruit to prevent bruising. Dr. Manoj Karkee at the WSU Center for Precision and Automated Agriculture (CPAAS) in Prosser, WA says that these two things are the obstacles for mechanical apple harvesters to overcome. He is designing a machine with a computer that will see correct colors, focus in on the apples, and an arm that plucks them off the tree like a human hand. Machines of this type will not be on the markets for a few years, and may not be feasible for all growers to use. See: “WSU engineers, scientists prepare to test apple-picking robot,” M. Murray, WSU News, 2015 here. See also: “The rise of the apple picking robots,” D. Kroman, Crosscut, 2015.

Replacing people entirely with automated machines is not feasible at this time and scientists are still working on fruit quality issues regarding harvest machines. Growers are looking to lower-tech automation, which still utilizes human labor. Basic picking platforms can increase productivity, by not using ladders. They will allow people to continue to pick into traditional picking bags, and empty fruit themselves into bins on the platform. An example is Bandit Xpress (made in Moses Lake, WA) that can be operated easily. See: “Machines offer a boost with apple harvest,” D. Wheat, Capital Ag. Press, 2013. Newer harvest aid machines include the vacuum harvester (DBR Conveyor Concepts) and Pluk-O-Trak (OESCO). See “The state of mechanical apple harvesting,” R. Jones, Growing Produce, 2015.

Dr. Paul Heinemann, Pennsylvania State University, is working on a lower cost harvest assist device (platform) that may be more feasible for smaller growers. His research focuses on combining manual and automatic harvesting, in two-person self-propelled platforms.  Dr. Renfu Lu, Research Leader for the USDA/ARS Sugarbeat and Bean Research Unit at Michigan State University is working on an apple harvest sorting system that will sort apples into 2 or 3 quality grades in the orchard. This is designed to save time and money by not sending lower quality fruit to the packinghouse, as well as reducing the incidence of postharvest diseases from introducing contaminated fruit. It uses a computerized color imaging technology, as well as new designs for fruit handling, grading, and bin filling. Currently, postharvest storage, sorting, and packing costs are high due to damaged and infected fruit coming in to the packinghouse from the orchard. See: “Apple harvesting sorting system makes debut‘” G. Pullano, Fruit Grower News, 2013. See also: “In-orchard sorting: A prototype machine divides apples into fresh, processing, and juice grades,” R. Lehnert, Good Fruit Grower, 2013.

Other Automation Research

Dr. Matt Whiting, WSU, Irrigated Agriculture Research and Extension Center, Prosser, WA has conducted trials on mechanization in sweet cherry orchards. His team has used mechanization for pruning, topping, and hedging of trees. He is also testing a shake and catch harvest device for sweet cherries. Using this device, his team saw a four-fold increase in harvest efficiency. Dr. Whiting’s team has also been conducting research in the field of precision pollination of sweet cherry by using a pollen solution applied to the flowers using a commercial electrostatic sprayer. See: “Precision pollination: Mechanical pollination could end use of chemicals or hand labor for thinning,” M. Hansen, Good Fruit Grower, 2015.

Dr. Vince Jones, entomologist at WSU Tree Fruit Research and Extension Center, Wenatchee, WA has collaborated with a group of researchers on the development of an automated insect trap that can catch and identify insects, and send the information to orchard managers. The trap has an electrical grid, GPS system receiver, and a radio transmitter, and conventional trap lures. See: “Automated insect traps aim to simplify pest detection,” B. Hoffman, WSU On Solid Ground, 2012. See these Good Fruit Grower articles also: “Remote pest management with automated traps: With an electronic trap and wireless network, growers can spend less time scouting in the orchard,” P. Mitham, Good Fruit Grower, 2014; and “Automated trap simplifies research,” R. Lehnert, Good Fruit Grower, 2014.

Technology and Automation in the Research and Development Stage

Visit the WSU Center for Precision & Automated Agricultural Systems (CPAAS site) and the Comprehensive Automation for Specialty Crops (CASC site.)  Research is currently being conducted on the following projects:

    • Vision-aided machines that measure fruit on the tree and detect size and numbers for crop load estimates, determine fruit colors and ripeness for harvest
    • 3D reconstruction of trees for pruning
    • Humans and robots working together for high tech. harvest
    • Apple in-field sorting and harvesting equipment
    • Bin dog for harvest
    • Tree caliper and counter
Technology and Automation in the Testing Stage-In Use by Some Growers

The following technologies are being tested and used by some growers:

  • Precision canopy and water management of specialty crops through sensor based decision-making (Sensors will determine tree stress and turn on and deliver the right amount of water when trees need it.)
  • Solid set canopy delivery systems and smart sprayers for chemical and nutrient applications.
  • Automatic Platforms (Used for harvest, pruning, thinning, placing insect traps, etc.)
  • Mechanical harvesters (Apple and Cherry)
  • Pest Management-automatic insect traps with lures, that catch, count, identify, and monitor insects.  See Precision pest management, CASC page.
  • Autonomous orchard vehicles, self steering and driving for orchard monitoring with cameras, and for workers on platforms needing to slowly go down rows working in the trees.
  • Unmanned aerial vehicles (UAV’s) (Drones) for scouting orchards, crop estimates, detecting soil moisture, tree stress, counting trees, checking for pest damage, water and nutrition issues, chasing birds from trees
  • Knot-tying robots for trellis top twining
  • Night harvesting apples with platforms and lights
  • Harvest management information system for specialty crops, (digital weighing system, pickers wear id bracelet, fruit weight and drop location is measured and recorded)
  • Bird repellent using automated lasers
Technology and Automation Currently Being Used by Growers

The following technology and automation is being used by growers today:

  • Platforms- to replace orchard ladders (Multipurpose)
  • Harvest assist machines (limited use to date) –Researchers are currently addressing the issue of fruit bruising during mechanized harvesting, as they develop sophisticated machinery for harvesting fruit.
  • Decision Aid –Environmental sensors of all types collect data to help growers with decisions related to irrigation, pest and disease management
  • Environmental measurements (Air temperature, relative humidity, solar radiation, wind, leaf moisture, rainfall, soil temperature, soil moisture, etc. Data is collected and sent to mobile devices in real time)
  • Mechanical pruning and hedging
  • Mechanical thinning – Hand held string blossom thinners, and tractor mounted thinners.
  • Automated irrigation systems- will turn on the right amount of water when it is needed. (WSU Irrigation scheduler App will let growers know when to turn it on)
  • Packinghouse and warehouse – New technology that sorts and packs fruit more quickly and accurately; Automated storage retrieval system for warehouse. (See Growing Produce article link “Matson fruit automates storage with robotics” below)
  • PET Tiger software-tracks worker productivity (maps worker productivity at any given time, and over time. Can use for labor decisions, payroll, accessible on any device.) (software)


Tree fruit production is a highly competitive industry worldwide, so growers may be required to use more automation and technology in their orchard operations to remain competitive in the international market. Washington State fruit growers compete domestically and internationally and are the top apple, pear, and cherry growing state in the country. (NHC fact sheets).

When trying to decide on whether or not to use automated machinery and new technology in your production system, realize that it will cost more at the start to purchase the equipment, and it will require an adjustment for workers to learn to use the new technology and equipment at first. In many situations, the new technology will save time and money in the long run. Consider tree size and row spacing, training systems, etc. when choosing automated systems for already established orchards. New high-density orchard production systems with narrow canopies are well suited for automation. Not all technologies are feasible for all growers and systems though, and growers will have to find the tools that will most benefit their operation. New tree fruit blocks can be established with automation and technology in mind, and planned and designed accordingly.


General Automation Resources

Comprehensive Automation for Specialty Crops (CASC) research

Comprehensive automation for specialty crops program (CASC), WSU scientists are collaborating partners.

WSU-CPAAS Research

See the WSU Center for Precision & Automated Agricultural Systems (CPAAS) 2014 Yearbook to learn about recent research. A total of 22 research projects are summarized in this yearbook. The yearbook can be viewed online or downloaded.

Other WSU resources


Trade Articles


Other Universities

Apple Automation Resources

WTFRC Research Reports

WSU CPAAS Research

Trade Articles

Technical Articles

Pear Automation Resources


Stone Fruit Automation Resources

CPAAS Research

Technical Articles

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