Wine Industry Newsletter

Snail baiting demonstration

The issue of snails in vineyards across multiple regions in WA is proving to be a persistent one.

Anecdotally it is believed that producers are not applying baits at the correct time (Autumn) mainly because of vintage respite, when snails are beginning to become active and laying eggs. Compounded by the wet and cool, spring has no doubt provided snail populations with ideal conditions to populate this year.

The purchase and application of baits is an expensive process; this activity funded by Wine Australia’s Regional Program (administered by Wines of WA) aims to improve producers understanding of the best methods of snail management through demonstration.

The activity consisted of two parts; a laboratory trial, and a field trial focusing solely on the brown garden snail (Cornu Aspersum).

Laboratory

A series of snail enclosures were set up with ten snails in each, replicated by three enclosures per treatment. Six (including a control) bait products were applied for each enclosure (see Table 1) and after 48 hours baits were removed and weighed.

Table 1: Baits used in experiment

Trade name

Active ingredient

Control

Chicken pallet

Protect-Us™

10g/kg Iron Powder (organic product)

Metakill

50 g/kg Metaldehyde

SlugOff®

30 g/kg Metaldehyde (lentil shape pellet)

Slugout®

18g/kg Metaldehyde

Baysol®

20g/kg Methiocarb (registered for home gardens)

Snails of various sizes were collected for this experiment from a bait and spray free vineyard and multiple home gardens.

The snails fasted on a moistened substrate of cotton bed sheet for 48 hours then placed into an enclosure on a fresh moistened substrate.

Snails were placed in the middle of the enclosure and baits were laid out around the snails to encourage feeding.

After 48 hours the baits were removed, dried and weighed to calculate quantity of bait consumed.

Counts of live and deceased snails were conducted at day seven by putting the snails in the middle of the container and the ones that didn’t move 24 hours later were counted as deceased.

Snails within different bait treatment enclosures
Snails within different bait treatment enclosures

Results and discussion

Data was analysed using analysis of variance (ANOVA) that incorporated the factorial treatment structure.

Figure 1 illustrates the percentage of bait consumed averaged across the three replicates. Bars with the same letter do not differ significantly (P<0.05) according to Fisher’s least significant difference test.

Figure 1 Percentage of bait consumed per treatment
Figure 1: Percentage of bait consumed per treatment

The graph clearly shows there is significantly less bait consumed compared to the control (P<.001).

Of the baits, Protect-Us™ was consumed much more than the other four baits.

Figure 2 Number of deaths per treatment
Figure 2: Number of deaths per treatment

As Figure 2 shows, all baits were effective in killing snails when compared to the control (P<0.001). All baits except for SlugOff® caused significantly more snails to die than the control. Protect-Us™  caused the highest death rate, followed by Baysol®. Different concentrations within the metaldehyde based baits did not cause significant differences in mortality rates when compared to each other.

No strong relationship between the amount of bait consumed and mortality rate was observed.

Field

The field component of this activity was set at a commercial vineyard in the Margaret River wine region. A one hectare block of Sauvignon Blanc was utilised to demonstrate the effectiveness of two bait products; an iron complex based bait representing an organic product and a metaldehyde based bait representing a conventional product.  Three separately designated treatment areas were marked and baits applied at three different timings; March, May and September (as shown below).

These baits were manually applied (at label rate), Metakill was applied at 10 kg per hectare and Protectus™ at 15kg per hectare.

Field trail design
Field trail design

The middle panel for each treatment zone was monitored for snail numbers in both the canopy and vineyard floor. Microcosms were also installed into each treatment zone with 20 snails enclosured so to observe mortality rate of a contained population within the zone.

Microcosm
Microcosm

Snail numbers (both live and dead) were observed in the monitoring panels as well as in the microcosms before application, 24 hours later and 7 days after bait application.

This vineyard was also used to collect monthly samples for dissection to monitor life cycle stages that may indicate timing of egg laying (via albumen gland size). The snail management demonstration commenced in March 2021 and will be completed in February 2022.

Results and discussion

The results from this field component are for demonstration purposes only as there is not sufficient replications for the data to be statistically validated.

There is a trend that the number of snails in the canopy gradually increased from March to September.

During counting it was observed that there were no small snails (shell width less than 10mm) in March, however many snails of this size were observed in May and September. There were also more medium sized snails (between 10mm-15mm) from May to September.

The following figures illustrate the observations made in March (Figure 4), May (Figure 5) and September (Figure 6) of snail populations within the monitored panels.

Figure 4: March baiting observations.
Figure 4: March baiting observations.
Figure 5 May baiting observations.
Figure 5: May baiting observations.
Figure 6 September baiting observations.
Figure 6: September baiting observations.

No snails were observed in the canopy in March, this is attributed to the block being harvested days before the count. There were also relatively low numbers found on the vineyard floor and few deaths.

May populations increased but very few signs of snail death after the baits were applied.

September observed an influx of snails in the canopy and on trunks and after seven days, both baited treatments showed a decline in snails on the vines and almost equal proportions of dead snails to those remaining on the vines.

Observations from the populations enclosed in the microsomes are summarised in Figure 7. The timing of these counts mirrored those made in the monitored panels.

An anomaly should be noted in regard to the May data set being that sheep within the block at the time did disturb the microcosms and potentially allowed some of the enclosed snails to escape.

Figure 7 Microcosm observations
Figure 7: Microcosm observations

The baits appear to have similar efficacy but in terms of ideal bait timing, it is difficult to comment based on variables such as vegetation within the microcosms providing an alternative food source and weather events influencing activity.    

Life cycle observations from this activity will be reported in a future newsletter edition.

For more information on this work, contact Yu-Yi Liao, Technical Officer or Richard Fennessy, Research Scientist.

Acknowledgements

This activity is funded via the Wine Australia Regional Program which is administered by Wines of WA. Support from Mike Sleegers at Cowaramup Agencies and AHA Viticulture in providing access to a site and bait products is also greatly appreciated. 

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Wine tasting workshops complete for 2021

Since October, Richard Fennessy and Yu-Yi Liao of DPIRD’s grape and wine research team have conducted wine tasting workshops in the Swan Valley, Margaret River and Great Southern. Through these events 50 producers have taken the opportunity to taste a number of trials produced from the 2021 vintage.

Emerging varieties

DPIRD partnered with a Swan Valley producer who currently has new plantings of Prosecco, Mencia and Nero d’Avola to produce small-lot wine batches (~dozen bottles) of these varieties to demonstrate their potential. The Prosecco was produced using the traditional method, the Mencia was picked at two different maturities for rosé and medium bodied red while the Nero d’Avola was made into a single batch of medium bodied red.

Overall, the Swan Valley producers who tasted these wines were excited about each of the varieties and their potential for the region. Prosecco was noted as being a strong yielding variety and tolerant to the warm/hot conditions typified by the Swan Valley. The style was seen as a perfect offering to visitors of the region and local consumers wanting an approachable fruit forward sparkling wine within the $20 - $30 price range. Discussion was had on the most commercially effective way to produce this sparkling style and the winery equipment required.

The two Mencia wines were commended and fit within a style of early drinking red wine but reviewing the pH and TA of the fruit showed some concern of the ability of this variety to retain acidity. Acknowledging that all these varieties were grown in the 2020-21 season for vegetative purposes rather than for fruit quality may have been an influencing factor. In contrast the Nero d’Avola did not require any acid adjustment and the wine quality was rated high, leading to a group consensus that this variety presents an exciting proposition for the region.

Chardonnay winemaking trial

A 200kg parcel of Chardonnay from Margaret River was split into 12 separate winemaking treatments, the purpose of this trial was to demonstrate in isolation how these techniques impact wine attributes. The treatments consisted of:

  1. ‘Control’ – following a neutral winemaking procedure this treatment represents a reference to compare the following treatments and provides the foundations to the winemaking approach for the following wines.
  2. ‘Skin contact’ – must kept at 4°C for four days before pressing.
  3. ‘Light solids’ – juice was racked to 97 NTU prior to inoculation (control was racked at 48 NTU).
  4. ‘Heavy solids’ - juice was racked to >1000 NTU prior to inoculation.
  5. ‘High fermentation temperature’ – fermented at ~23°C compared at 16°C of the control.
  6. ‘Early pick with deacidification’ – picked 11 days earlier than the control and deacidified.
  7. ‘Late pick’ – picked 12 days after the control.
  8. ‘Yeast 1’ – inoculated with Level2 Biodiva™ from Lallemand Oenology (Torulaspora delbrueckii) and QA23™.
  9. ‘Yeast 2’ – incolated with Anchor yeast product Exotics Mosaic (hybrid yeast strain of Sacch cerevisiae x Sacch paradoxus).
  10. ‘Wild ferment’ – no SO2 added at juice stage.
  11. ‘Low diacetyl MLF’ – inoculated with CHR Hansen product Viniflora® CiNe™.
  12. ‘High diacetyl MLF’ – inoculated with CHR Hansen product Viniflora® CH35.

Of the 50 producers that tasted these wines blind, there was a number of consistent preferences noted between the different regional groups. The treatments that scored well included yeast 2, wild ferment, skin contact and high diacetyl MLF. The characters that were noted on these treatments were they provided greater complexity and acid balance compared to the control.

Cabernet clones and selections

A block of Cabernet Sauvignon (clone SA126) in Margaret River was grafted over to 14 different clones and selections in 2019. The 2021 vintage provided the first opportunity to harvest fruit from this randomised and replicated block for small-lot winemaking. Each clone/selection was harvested from at least three different replicates and made into wines using a standardised winemaking procedure. The wines were presented blind to 40 producers, in terms of preferences from these groups there was a large spread but at least two groups showed some consistency identifying Roche 9-7 and SA126 as preferred clones. This work will continue into further seasons with increased measurements taken on vine performance.

Merlot clones

A Margaret River producer collaborated with DPIRD in providing fruit from three Merlot clones (D3V14, 181 and Q45) grown from separates blocks on a single vineyard. Tasting these wines with the producer groups showed the newer clones of 181 and Q45 produced riper, denser wines in the dark fruit spectrum compared to the widely planted D3V14.

Shiraz shading trial

DPIRD was provided fruit from a Frankland River vineyard that had installed shade cloth to the fruit zone on a row of Shiraz and an adjacent row without the shade cloth. The objective of the shade cloth is to minimize sun exposure and consequently reduce the incidence of berry shrivel and sun damaged fruit. Temperature data loggers were also installed in the adjacent canopies which surprisingly showed no significant differences between each other.

The impact of the shade cloth was shown to slightly slow down maturity and retain acidity. Descriptors from those who tasted the wines found the shaded wine to have more obvious spice and be of a refined elegant style compared to the richness of the control.

Acknowledgments

These workshops and the Cabernet clone/selection activity were funded via the Wine Australia Regional Program administered by Wines of WA. The following organisations are thanked for their contribution to these activities; Fogarty Wine Group, Burch Family Wines, Swinney Vineyards, Voyager Estate, Lallemand Oenology and CHR Hansen.

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Subsidised SWA certification training opportunity

Via the Wine Australia Regional Program, Wines of WA is supporting up to 30 producers with subsidised registration fees to attend upcoming Sustainable Winegrowing Australia (SWA) certification training.

This training allows SWA members to be independently audited against Australian Wine Industry Standards of Sustainable Practice – Viticulture (AWISSP-VIT1) and/or Australian Wine Industry Standards of Sustainable Practice – Winery (AWISSP-WIN1).

The AWRI has been engaged to deliver two separate online certification training workshops which attendees’ will be able to attend from their own computers. These are scheduled as follows:

  • Workshop group 1

    • 8.30am – 11.30am, Monday 17 January 2022

    • 8.30am – 11.30am, Tuesday 18 January 2022

  • Workshop group 2

    • 8.30am – 11.30am, Thursday 20 January 2022

    • 8.30am – 11.30am, Friday 21 January 2022

Training will be held by a qualified and Freshcare-registered AWRI trainer, covering all the necessary elements of the program including the processes and plans required to pass an audit. Trainees are provided with a set of customisable templates and resources to support the preparation and maintenance of the program.

Margaret River producers interested in registering an expression of interest for this training opportunity are asked to contact Margaret River Wine Sustainability Engagement Officer, Eloise Jarvis.

Producers outside of the Margaret River wine region can send expressions of interest to Richard Fennessy, DPIRD Research Scientist.

Please note that registrations to these training workshops will be provided on a first come first served basis and only one representative from a business can register.

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Wine industry podcasts

With harvest only a few months away, what better time to update your podcast playlist for the long vintage hours ahead.

The following is a collection of podcasts which feature technical elements of viticulture and winemaking and also human-interest stories relating to the wine industry.

AWRI Decanted

Interviews held by host Drew Radford (experienced reporter and broadcaster) meeting with scientists working for the Australian wine industry and producers who are putting wine research into practice. The first series of AWRI Decanted focuses on the fascinating world of wine flavour.

Australian Grape & Wine by Australian Grape & Wine

Information for Australian grape growers and winemakers, including domestic and international wine policy updates, the inside word directly out of Canberra, and conversations with some of Australia's most experienced industry participants on the things that matter to Australian wine producers.

Between the Vines - A podcast brought to you by the Lake Erie Regional Grape Program

Focuses on timely viticulture, business management, and Integrated Pest Management issues to help vineyards achieve commercial success. The podcast covers timely topics and research updates throughout the year. This regional Extension team is a collaboration between Penn State and Cornell University.

Grower, Maker, Researcher - Wine Industry Insights by ASVO

Created by the Australian Society of Viticulture & Oenology, funded by Wine Australia through the Extension and Adoption program. The podcasts take a very practical approach, talking to highly regarded growers, winemakers, and researchers about current best practice and what changes to expect in the near future.

Real Wine People by Ben Gould

Long form conversations with vineyard & wine folk about their stories and experiences within the fast-changing wine landscape.

Sustainable Wine

Interviews with people from across the wine value chain, mostly winemakers and growers, on key sustainability issues in the wine industry.

Sustainable winegrowing with Vineyard Team

The latest in science and research for the wine industry, which provides in-depth technical information on topics like integrated pest management, fruit quality, water conservation, and nutrient management from experts like Dr. Mark Fuchs of Cornell University, Dr. Michelle Moyer of Washington State University, Cooperative Extension Specialists, veteran growers, and more. This podcast will help you make smarter, sustainable vineyard management decisions to increase efficiency, conserve resources, and maximize fruit quality.

The Inside Winemaking Podcast by Jim Duane

Napa Valley winemaker, Jim Duane, hosts interviews with some of the top winemakers in California and beyond. Each episode features a winemaker, grape-grower, or technical wine pro and dives deep into their background and expertise.

The wine show Australia by Simon Nash and Jill Upton

Interviews with Australian wine industry personalities and uncover their stories & amazing tales.

Ungrafted by Icy Liu

A series of conversations with scientists, winemakers, and industry professionals who are dedicated to pushing deeper into biodiversity, regenerative agriculture, reducing the carbon footprint of wine, increasing diversity in the wine business and more.

Vinecast by James Scarcebrook

Conversations between guests from the wine industry and host James Scarcebrook (aka The Intrepid Wino) about their backgrounds, influences, and philosophies on wine.

Wine Unearthed by Margaret River Wine Association

This 5-episode podcast made in 2019 tours you through the lauded Margaret River region with rich sounds and even richer characters featuring stories of Aboriginal cultural custodian, big wave surfer, family winery from Margaret River and wine tasting with Peter Forrestal.

Winederlust - Exploring Aussie Wine Regions by Jeanene

Each series visits a handful of Aussie wine districts, meeting locals, visiting cellar doors, talking about the flagship wines and finding out what else to do there, including for the kids. There will also be an episode each series interviewing a well-known person about their favourite region.

 

 

Future events

Functional Biodiversity Enhancement - the native solution

In January, Margaret River Wine will be hosting Dr Mary Retallack to virtually deliver this full day workshop. Dr Retallack is an expert in biodiversity specifically in regard to viticultural practices and is based in South Australia. Topics to be covered include:

Functional Biodiversity Enhancement – the native solution

An introduction into the use of native species within and around vineyards to create biodiverse ecosystems using insectary plants. Mary will discuss practical aspects of implementation, long term benefits and provide examples of local native insectary plants.

Biological Control of Insect Pests

With a focus on Western Australian issues, the concepts, and practices of managing pests through biological control as a key component of arthropod-mediated ecosystem services will be discussed. ‘Biocontrol’ of pests throughout a season is delivered by a whole range of predatory arthropods.

Biodiversity Action Planning

Development and application of biodiversity action plans for vineyard properties: within and adjacent to vineyards, regeneration and maintenance of remnant bush and rehabilitation of water courses and riparian zones.

Margaret River Wine and Dr Retallack have invited local experts and service providers to each presentation, bringing their depth of knowledge and regional perspective, providing you with an opportunity to discuss topics within a local context

When: 8.30am – 3.450pm, 19 January 2022

Where: The HEART Studio Theatre, 47 Wallcliffe Road Margaret River

Morning tea/lunch included.

Register here.

Australian Wine Industry Technical Conference

The 18th AWITC and WineTech Exhibition will be held 26-29 June 2022 in Adelaide, South Australia. Registration will open in February 2022. The program is currently being developed and will incorporate the Australian Grape and Wine Outlook Conference.

More information is available at https://awitc.com.au/