Connecting Under the Kiwifruit Canopy
Survey Firm Draws on Subscription-Based Model to Scale-Up Ag Mapping
Maintaining a consistent quantity of high-quality produce to deliver strong compensation for New Zealand's highly regulated kiwifruit industry is a matter of climate, skill and precision.
Grown in New Zealand, these sweet, unique berries are sold through Zespri International Limited, the world's largest marketer of kiwifruit, selling to more than 50 countries. It's a business model requiring a symbiotic relationship with around 2,800 New Zealand growers, with licenses to grow kiwifruit valued at a premium.
Zespri licensed growers must undergo regular audits of the orchards to ensure they are growing kiwifruit within their authorized production area. Increasing their planted areas without a license can result in significant fines. The means and methods for conducting these audits have adapted over the years, thanks to Matt Flowerday, founder of GPSit, a precision land mapping company.
As the son of kiwifruit-growing parents, Flowerday understands the importance of orchard maps for growers and to Zespri. He founded GPSit with the vision to map orchard production areas, or blocks, using GNSS technology rather than traditional surveying methods.
Today, the firm is contracted to survey all Zespri orchards in New Zealand. While it continues to rely on GNSS to support these audits, GPSit's tools have evolved considerably in its quest for accuracy and repeatable results under the kiwifruit canopy.
Kiwifruit is grown in blocks. A typical kiwifruit block is made from various structures, including strainer and support posts, leader and canopy wires, and wire support cables. These form rows, end assemblies and overhangs that make up a production (block) area. The overall structure typically sits about two meters off the ground. A survey of a kiwifruit orchard requires measuring each block to ensure the block area matches the licensed areas.
Khan Greig, general manager for GPSit, said, "The cost of getting it wrong is quite onerous for everyone involved—that's why we need to have centimeter accuracy."
One of the biggest challenges of surveying kiwifruit blocks is the high shelterbelts that separate the kiwifruit blocks. The methodology for data collection has evolved over the years from mounting GPS antennas on vehicles to even putting them on motorized ATV bikes. But environmental, biosecurity, health, and safety hazards moved the process back to more conventional on-foot methods—a practice that continues today, though with a different mobile GNSS device.
For years, GPSit relied on conventional GNSS-enabled survey equipment but was challenged by ease-of-use and satellite visibility around the kiwifruit blocks, which could limit accuracy or cause significant delays in the data-gathering process. GPSit was also looking to scale its mapping services internationally, and due to the seasonality of their work, investing in traditional high-end GNSS units was cost-prohibitive.
While visiting the United States in 2017, Flowerday saw an early version of the Trimble® Catalyst™ GNSS positioning service with Trimble DA1 receiver, a subscription-based GNSS solution that provides professional-grade positioning as an on-demand service—the first commercially available, software-defined GNSS receiver. When Flowerday returned to New Zealand, he contacted Allterra, the authorized Trimble Geospatial distributor, to arrange a test unit. Allterra assisted with setup and has provided ongoing support.
Robyn O'Brien, mapping team lead for GPSit, recalled, "We tested one of the units and loved it. It's low cost, lightweight and easy to use. However, we found Trimble Catalyst with the DA2 receiver does much better than anything we've used in the past, reaching more stations than our previous survey solutions and obtaining lock faster."
Locked on to precision
While kiwifruit blocks vary, they are generally around 100 meters long. Entire orchards range from one-half to 85 hectares. For an orchard audit, a GPSit surveyor walks around each block with the Trimble DA2, setting up ground control points for a drone and gathering points around the perimeter of each block.
"The speed to lock is one of the biggest benefits of the DA2s," Greig said. "In some of the tricky areas around the dense canopy and high trees, we'd have to wait several minutes to get a lock. The DA2 does it in 10 seconds or less."
Once back in the office, the survey team uses Esri® ArcGIS® Pro desktop GIS software to create the orchard map and publish an Audit report for Zespri.
Currently, GPSit owns five DA2 systems with six trained surveyors. "It's so easy to use that our surveyors are ready to go in 10 minutes," Greig added. "The ease of use frees them up to focus on the logistics challenge of moving and measuring around heavily canopied orchard blocks, which are all different sizes and shapes."
Along with ground-based surveying, the GPSit team uses UAV technology to capture aerial imagery, typically at 120 meters (400 feet). GPSit combines the geometrically corrected ortho imagery with the survey data captured to create a highly detailed orchard map.
Beyond block audits, GPSit also works with growers to establish design and plan new blocks and orchards, positioning them in the optimal location for sunlight, wind protection, drainage and worker access to optimize a more sustainable use of the land. O'Brien confirmed, "We base our orchard designs off the land contours, drainage conditions, sunlight, and additional information provided to us by the grower. We use Esri's ArcGIS Field Maps application for infield data capture and developed a web app to author all the information we need in the field so that we can easily and precisely locate all of the block components. It's efficient and effective."
Greig concluded, "Zespri and the growers greatly appreciate the speed and accuracy with which we are able to complete these surveys. Thanks to the Trimble Catalyst with DA2 technology, we can scale up our survey operations which we need to as more mapping opportunities come our way."
Learn more about Trimble Catalyst.