January (No. 492)
Precision Viticulture – providing more benefits than costs (CRCV, On The Ground)
Precision viticulture is all about identifying and managing variability within vineyards. One of the major criticisms of precision management in viticulture has been the cost of implementation. Since the grape and wine industry first looked at this approach more than a decade ago, major progress has been made in its affordability. Precision management relies heavily on measurement and monitoring technologies and an increasing number of suppliers now offer various types of tools at prices that are commensurate with the benefits.
In addition, research has continued to refine the tools and discover new uses. Increasingly winemakers and grapegrowers are looking to precision viticulture to provide them with answers to questions such as ‘Which vines need more water or fertiliser?’, ‘Is the fruit ripening at the same rate throughout my vineyard?’ and ‘Is selective harvesting an economically-viable option?’ The Cooperative Research Centre for Viticulture (CRCV) has invested considerably in the development of precision viticulture through its research program and is now also involved in the transfer of this knowledge to grapegrowers, particularly through its Viticare Trials program.
CRCV and University of New England researcher, associate professor David Lamb, said remote sensing, an important vineyard monitoring tool, is providing more benefits than costs, evidenced by the increasing number of companies adopting the technology.
“At the end of the 2002-03 season we surveyed all of the major Australian remote-sensing providers and found that about 15,000ha or almost 10% of Australia’s vines had been imaged that season,” Lamb said.
“Growers were using the technology to support strategic monitoring of vine development, often for selective harvesting, irrigation management or to detect pests such as phylloxera.” While precision agriculture technologies have been widespread in broadacre cropping systems for many years, Lamb said the economic and environmental benefits were now becoming clear to the viticulture industry.
“Both yield and wine quality are major objectives for the Australian wine industry, so growers and winemakers need to do more than simply minimise vineyard inputs. This focus will only see the uptake of precision viticulture increase in the coming years,” he said.
Grower trials demonstrating precision viticulture
One of the ways the CRCV is supporting the application of precision viticulture in the industry is by incorporating aspects of the technology within its Viticare Trials project. This project involves more than 20 vineyard trials in Australia’s major winegrape production regions. The trials are addressing key regional issues such as irrigation and water-use efficiency, canopy management, fertiliser application, pruning, cover crops and pest and disease management. Groups of growers, regional associations, suppliers, liaison staff and researchers are working together on the trials to ensure the results will benefit participating regions.
Robinson, one of the major impediments to the adoption of precision viticulture is uncertainty by growers about how the tools can be used in addressing these issues to improve their vineyard profitability.
“Considerable research has been done, yet to accelerate adoption of precision viticulture more regional experiences, practical understanding of the technology and recognition of the benefits of understanding vineyard variability need to be demonstrated,” Robinson said.
Incorporating precision viticulture into each Viticare Trial is starting to achieve these aims.
“We have started EM38 soil surveys and RTK GPS at about half of our trial sites. We are also implementing remote sensing and creating vine vigour maps at a large number of trial sites,” she said.
“At a number of sites in the Riverina, Sunraysia and McLaren Vale we have used the data to alter our trial design and to pinpoint where to take measurements for the season.
“This is really important because the trials aim to give regional growers an idea of how they can improve their management and what the outcomes will be. Precision viticulture is allowing us to refine our measurements and provide more meaningful data.”
She said working with suppliers and other CRCV researchers, including Dr Rob Bramley and Dr Kerstin Panten, had provided the Viticare Trials team with a better understanding of how to analyse the data and how it could be used.
The aim is to conduct precision viticulture in at least one form on most trial sites over the next two years.
Precision viticulture helps manage yieldAt Apostle’s Yard vineyard in the Riverina region of NSW, the use of precision viticulture tools has led to consistent grape quality and, as a result, a good relationship with winemaker Miranda Wines. And this has, in turn, led to sustainable fruit prices. Vineyard manager Charlie Elliston said of the 120 hectares at Apostle’s Yard, 32 hectares were currently associated with trials using the tools of precision viticulture.
Elliston said the trials were launched after part of the vineyard was converted to drip irrigation in 2003. “After installing drip we began looking at the mid-row. We wanted to manage it in the most cost-effective manner possible to improve soil structure, aeration and trafficability,” he said.
“There wasn’t much information available about management of the mid-row area in the Riverina region, so we decided to set up some trials of our own as part of the CRCV’s Viticare program.”
Elliston organised an EM38 survey to learn more about the variability of his soils, and with the backing of the CRCV he is also setting up neutron probe, gypsum block and mid-row temperature monitoring trials. This information will be useful when additional sections of the vineyard are converted to drip irrigation.
Elliston was also motivated to look more closely at his vineyard soils after a 28-hectare patch of Shiraz displayed yield problems. “The canopy was performing poorly and the yields were low (7 tonnes per hectare), so, using the vigour maps, we targeted the areas for sampling, did some soil tests, dug some backhoe pits and found a nasty dispersion layer,” he said.
“Once we had that knowledge, we started managing the soil in different ways, such as the use of cover crops. Now the ‘problem patch’ is producing 12 tonnes per hectare.”
He said relying on guesswork would lead to unpredictable grape quality results and diminished fruit prices. “It’s possible to get the fruit quality and colour that wineries want at 12-14 tonnes per hectare, but you have to know what’s happening in your soil,” he said.
Elliston is also conducting irrigation trials to glean information about the economic value of converting from flood to drip.
“We knew we’d see a drop off in tonnes and quality while vine roots adapted to the new watering regime, so this year I’ve selected certain rows that I will continue to flood irrigate at critical times in the season,” he said.
“I will compare these vines with vines that are just drip irrigated and judge how the vines are coping with the conversion.”
Charlie will take into account vineyard inputs, vine health and fruit quality and put together a financial analysis of the conversion process.
“It will be valuable data for the region because there is a belief that converting to drip is expensive, but I think I will find that despite that conversion stage, drip quickly pays for itself. Simply having the ability to manipulate fruit quality with irrigation is an extremely valuable tool.”
At Apostle’s Yard vineyard, EnviroSCAN Diviner 2000 soil moisture monitoring technology is utilised and regular petiole testing is carried out.
Network of enthusiasts to share precision viticulture experiencesAnother new project has recently been established by the CRCV to support the adoption of precision viticulture. It will bring together enthusiasts including consultants, grower liaison officers, growers and extension specialists in Griffith, Mildura, Riverland and Heathcote and will be conducted with assistance from the Viticare Trials project.
Each of the four groups will apply the tools of precision viticulture to a vineyard block, extending knowledge to producers and consultants providing them with the opportunity to evaluate the potential use of the precision management approach. The findings from these four blocks will also be used in the development of a new Viticulture Research to Practice‚ handbook that focuses on managing vineyard variability.
While the project has only just started and the groups are currently being assembled, it is aiming to give growers and wine companies first-hand experience in the application of various tools for precision viticulture, a better understanding of the costs and benefits and expertise in more-precise vineyard management.
The focus of the project is managing variability to improve quality and profitability and an emphasis will be on the analysis of yield maps, remote sensing and EM38 surveys to allow the groups to make their own decisions about how to use the information to deal with vineyard variability in the most effective manner. The project is being coordinated by Greg Dunn from the Department of Primary Industries Victoria and Viticare Trials coordinator Sheri Robinson.