North Coast vineyards see more drone use as agriculture market soars

A Napa Valley company that has been taking aerial imaging of vineyards to new technological heights for a decade and a half has formed a strategic partnership with grapegrower-oriented startup makers and operators of unmanned aerial vehicles, often called drones.

It's the second significant foray in recent months that brings the fast-growing field of agricultural drones to the North Coast.

The deal pairs image processing by Angwin-based Scientific Aerial Imaging Inc., better known as VineView (, with drones built by Halifax, Nova Scotia-based SkySquirrel Technologies ( then marketed and flown by Napa Valley's Hawk Aerial ( Hawk Aerial has plans for piloting drones for vineyard operators or selling drones that can be piloted largely autonomously by designating a flight path on a virtual map of the vineyard.

“We think that is the most exciting part, that vineyard operators can fly as often as they want and send images to VineView for processing,” said Bryan Soderblom, CFI, CFII, MEI, VineView's lead pilot and marketing director.

Five-employee VineView bases its sensor-festooned, full-sized single-engine planes at Angwin Airport–Parrett Field atop Howell Mountain on the eastern slopes of the valley. VineView has been working with SkySquirrel for two years to calibrate the drone systems it builds and analyze its clients' data.

SkySquirrel also has outposts in Switzerland and next to VineView at the Angwin airport. VineView's arrangement with Hawk, a Napa Valley-based operator and marketer of SkySquirrel's drones, developed over the past few months. The deal allows VineView to work with more clients who think having people in planes taking images of crops is too expensive, Soderblom said.

“We found drones most-efficient for smaller- to medium-sized vineyards - less than 100 acres,” he said. “Above that, it's more efficient with an airplane.”

The aerial robots VineView works with can capture images at a rate of 1 acre per minute, covering 20–25 acres on a battery charge. By comparison, VineView's plane-mounted sensors grab shots over 100 acres of vineyard might take about 10 seconds. Commercial drones have limited operating altitude under 120 feet by new Federal Aviation Administration guidelines, but that results in much higher resolution for crop imaging, Soderblom said.

“There is still market out there for airplane-based imaging, but I think drones will increase in use for smaller vineyards,” Soderblom said. “As battery life increases, drones will become more-efficient for larger vineyards as well.”

Depending on what imaging is needed and other parameters, the cost of airplane-based imaging and analysis of the hyperspectral images can be $10–$15 an acre for enhanced vigor index, or EVI, mapping of vine health up to $35–$40 an acre for RedLeafMap to show which vines are stressed by leafroll and red blotch diseases.

The EVI service, and higher-resolution PureCanopy EVI, builds on the normalized difference vegetation index, or NDVI, developed in 1992 by research at Robert Mondavi Winery. The difference is that EVI imaging isn't dependent on the time of day the image is captured, soil variations or shadows for comparison of vine conditions over time.

Other VineView imaging services are mapping vineyards by infrared, which helps in classifying vines for EVI analysis, and to show how vines are dealing with stress from lack of water. Modern winemaking has tended to varying forms of water stress to coax more vine resources into the grapes, but too much stress could be counterproductive.

Most of the cost of these services is in the image processing, Soderblom said. Airplane-taken images from 100 acres might take six to seven hours to process. Because drone images have higher resolution, the processing time is longer for comparable acreage, he said.


The global market for UAVs is projected to soar in the next few years, with agriculture among the top industries for these skybots, according to major research firms and financial analysts.

India-based Market and Markets in November figured global demand would grow from an estimated $13.2 billion last year to $28.3 billion by 2022.

PwC's Drone Powered Solutions group in May pegged the business and labor value drones could replace at $127.3 billion globally, based on 2015 values. While UAV home delivery of packages has been grabbing headlines, the biggest industry penetration is projected to be in infrastructure ($45.2 billion), followed by agriculture ($32.4 billion) then couriers and other transport ($13.0 billion), according to the “Clarity From Above” study.

Amazon's tests in drone delivery have shaved the $2–$8 cost of U.S. ground delivery by truck in a 6-mile radius down to 10 cents by drone, the PwC report said. And infrastructure and agriculture could benefit from real-time monitoring of rapidly changing and sometimes unpredictable conditions over a wide area, without the cloud-cover limitations of satellite imagery that's been used until recently.

Shipments of agbots for sky and land are expected to rise 18.6 percent in the next eight years, according to a Jan. 5 report by Dublin-based Research and Markets together with The Robot Report. The number of units shipped annually is projected to increase from 32,000 last year to 594,000 in 2024, when annual sales are forecast to reach $74.1 billion.

In addition to aerial imagery, farmbots are finding their way into roles such as driverless tractors and management of soils, crops, forests and livestock, the study said.

“The rising demand for agricultural robots is being driven by a number of factors, including global population growth; increasing strain on the food supply; declining availability of farm workers; the challenges, costs and complexities of farm labor; changing farmlands; climate change; the growth of indoor farming; and the broader automation of the agriculture industry,” said research analyst Manoj Sahi.

A labor shortage on the North Coast in the past few years, plus rapidly improving technology, has led to increasing acceptance among makers of higher-end wine for more automation in vineyards and wineries.

Once considered a tool mostly for cheap wine, mechanical harvesters are now finessing off the vines some of the North Coast's choicest grape clusters. Far fewer broken berry skins and less MOG - “material other than grape” such as leaves - are arriving at winery crushpads.

Then the arriving bins of grapes meet more bots. Optical grape sorters are bringing automation to the hand-sorting tables a number of makers of luxury-tier wine use to separate unripe and otherwise undesirable grapes from being crushed. Once the juice goes into the fermentation tanks, its “cap” of skins, seeds, stems and pulp that floats to the surface can be automatically punched down, or clear juice pumped over the cap, to match the winemaker's style.

Tankbots and barrelbots have been developed to speed the process and increase the water-efficiency of washing and sterilizing cooperage.


An example of the greater role of aerial agbots is crop spraying, and that has just taken off on the North Coast.

Yamaha Motor Corp. USA in April opened an office at Napa County Airport for spraying of agricultural land in Napa and Sonoma counties with its RMAX remotely piloted helicopter ( On May 18, a Napa Valley vineyard was the site for the first U.S. commercial crop spraying by UAV.

Yamaha's UAV team applied a fungicide for Napa-based Silverado Farming Company to stave off powdery mildew - a bane of grapegrowers.

Yamaha has been using RMAX choppers internationally for 19 years, but the quest to use them in the U.S. has been a several-year effort, the company said. The company has been working with the Federal Aviation Administration to receive appropriate certifications and testing the system in the field with the University of California, Davis. A representative from the California Department of Pesticide Regulation witnessed the RMAX flight.

“We've been diligently working toward this U.S. milestone for RMAX since 2012, when our research partnership with U.C. Davis began,” said Brad Anderson, a market development manager for Yamaha's Unmanned Systems Division. “It's gratifying to have earned support from both the aviation and agricultural communities. RMAX provides a unique and effective solution for spray applications, particularly for grape growers with vineyards on slopes or difficult terrain.”

Brittany Pederson, a professional pest-control adviser and viticulturist for Silverado, watched the May 18 spraying.

“The results of those trials and conclusions drawn from work at the Oakville Experimental Vineyards were pretty strong and gave us the confidence to begin our own experiments with the RMAX on privately owned commercial vineyards,” she said.

Benefits cited for UAS spraying include safer and more reliable application of treatments with no soil compaction. Applications via RMAX are said to have proven faster and more efficient than current ground spray applications from four-wheelers, tractors or workers on foot. It provides growers with more flexibility and accessibility to their fields, giving them another option for applications.

In December 2015 Yamaha received Part 137 Agricultural Aircraft Operations Certification from the FAA, said to be the first for an unmanned aerial system. That allowed Yamaha to begin agricultural spraying in the U.S., subject to approval by state and local authorities.

The RMAX system has been in service internationally since 1997 and has logged more than 2 million flight hours treating agricultural acres. Today there are 2,500 Yamaha RMAX helicopters flying worldwide, spraying more than 2.4 million agricultural acres annually. Crops treated include rice, wheat, soybeans and vegetables.


Jeff Quackenbush (, 707-521-4256) covers wine, construction and commercial real estate.

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