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A vineyard ecosystem thriving with IPM by Fischl

This article originally appeared in the August 2017 edition of Grapegrower & Winemaker.

 

If you’ve ever thought of moving toward a more organic growing model but don’t like the idea of risking it all in case your vineyard is ransacked by disease, it might be time to consider Integrated Pest Management. Camellia Aebischer reports.


Abstaining from the use of synthetic fertilisers can be a silent protest against a short-term solutions-based farming culture. As far as political divide, the practises tend to be heavy on the extreme ends of the spectrum: either a biodynamic and organic approach, or conventional agro-chemical farming.

Most winemakers who adopt a reductive approach to synthetic fertilisers and take care of the natural elements in the vineyard aren’t often able to leverage themselves with a category. Until now.

The French term, “la lutte raisonnee”, untranslatable, but loosely defined as “a reasoned fight” is a practise that is very close to organic, but allows the use of synthetic fertilisers at the personal discretion of the farmer.

The farmer is not bound by any rules, and his practise is usually distinguishable by a ladybird logo on the label, which is familiar in France.

Tom Munro, a winemaker and broker at The Other Bordeaux has translated many viticultural papers from French to English and explained the practise as “any strategy that results in a reduction in chemical inputs in the vineyard.”

“Things like using knowledge of ecosystems and pest lifecycles so that any sprays you use are most effective, or using innocuous wetting agents that make active ingredients more potent, or just reading weather forecasts correctly so that what you put out today doesn’t get rained away tomorrow. It’s just about acting intelligently and not just following the instructions on the chemical packets.”

A vineyard prior to Fischl’s consultation

For Australian’s and other countries, the closest practise (aside from just doing things your own way) is known as Integrated Pest Management (IPM). Although the practise focuses most on engineering the right type of ecosystem, it doesn’t shun the use of synthetic products where necessary.

What is IPM?

IPM is the process of controlling pests through a combination of practises, taking a preventative approach.

“Too many farmers are inclined to look at grapes and say ‘we’ve put this vineyard in, now how do we keep the outside world out of it?’” said Daniel Fischl owner and consultant at Eartrumpet, an IPM conversion business.

“Traditionally they’re taking a piece of native environment that’s subject to all these processes, clearing it, putting in an ancient monoculture and expecting to stop that outside world from coming back in.

“We need to set up a system so that the vineyards are naturally managed. That vineyard has a place in the ecosystem so we can’t just put up walls and nets to keep things out.”

Fischl’s consulting comes from a solid history in biology and plant research. After completing a PHD at UC Davis, Fischl worked in Napa Valley (where he met his wife), and the pair eventually moved to Melbourne to run Eartrumpet and a small wine label, Linnea.

“We need to set up a system so that the vineyards are naturally managed. That vineyard has a place in the ecosystem so we can’t just put up walls and nets to keep things out.”

 

IPM practises take in to account the ecosystem both inside the vineyard and in its surrounds. It considers environmental factors that are unique to the site/region and country, as well as the strength of the individual grapevines, to create a balanced environment and manage disease pressure.

Unlike organic and biodynamic practises, that sometimes utilise companion planting, IPM has the technique at its helm.

“We do a lot of research and study on the surrounding area, learning everything we can about plant and insect species, ecosystem dynamics and weather etc. We look at the dynamics of the environment around the vineyard and say ‘what can we do to encourage a beneficial environment here? And what kind of network can we engineer so that the vineyard is itself providing ecosystem services, and is in beneficial existence with the surrounding area?’.”

At Tarahill winery in Rutherglen, owners Andrea and Jonathan Hamer run an organic vineyard using biodynamic practises in combination with integrated pest management techniques.

“What we’re looking for in planting certain things, is to increase the bird and beneficial insects – hopefully. We look for things that flower and provide a habitat for them,” said Jonathan.

“We’ve put an orchard in the middle of the vineyard. Some grevillea’s and melaleuca’s, and planted mint bush, to encourage bird and insect life.

“The whole exercise is to get lots of different things living in the vineyard. We don’t just have a clover mix in the inter-rows we don’t mind having wheat and such.”

Although biodynamic practises are undertaken by Andrea and Jonathan, they remain realistic about where to draw the line. Having science backgrounds helps them to combine techniques. As Jonathan explained, “I don’t use yoghurt as my solution to mould in the vineyard.”

Fischl believes that organic viticulture can be risky. “The controversial word on organics is that not every vineyard can switch to it. Not that the farmers don’t have skills but some sites are just more prone to disease pressures than others.

“When you’re farming organic you want to be in a site with lower disease pressure, because the protection systems you use with organics are weaker than with chemical farming.”

As Tarahill is located in Rutherglen, the Hamer’s are growing in a phylloxera zone, which unfortunately can’t be managed through IPM at this stage, organic or not.

Tarahill in Rutherglen

Balancing a vineyard

Fischl spends a lot of time in airports, flying around the world to consult with his clients. On a recent trip to Mexico, he was met with the challenge of working out an IPM plan for an organic vineyard in a region laden with glassy winged sharpshooters.

“The problem was the bacteria (Xylella fastidiosa) in native surrounding plants, which can damage the grapes. The glassy wing is a perfect carrier for Xylella, which doesn’t affect many of the native plants” he said. So Fischl went in search of a locally-viable solution.

“We want to have lots of microorganisms in the vineyard, but don’t want to be in the situation where one mould is suddenly in the position to multiply en masse,”

 

Keeping local disease pressures at bay can be as simple as allowing multiple organisms to flourish. It may sound silly that to have less disease problems you should have more potential diseases, but the key is in the variation. At Tarahill, the Hamer’s manage their vineyard with this in mind.

“We want to have lots of microorganisms in the vineyard, but don’t want to be in the situation where one mould is suddenly in the position to multiply en masse,” said Jonathan.

“For example, there tends to be a fight between the various yeasts in natural winemaking and you hope that the best yeast for flavour is the one that wins.

“In [an organic] vineyard the approach is that you’re always going to have mould of some sort, but you don’t want to have powdery or downy as the one strain. If you have other moulds there they will basically deny the mildew its takeover.”

For Fischl in Mexico, bringing in a competitor for the glassy winged sharpshooter was key.

“We don’t have access to the wasps that we need to parasitise the eggs of the glassy winged sharpshooter in Mexico. But, what we did find is that some egg masses had been parasitised by a local wasp,” he said.

“The wasp wasn’t commercially available so we got in touch with the local school and funded a program to capture, identify and expand that species of wasp and get them to a commercial growing level.”

“For the organic vineyards there, we’re building some buffer strips in along the perimeters. Where the trees are that harbor the pests, we’re putting in a selection of native plants that are constantly flowering, to attract the local wasp species.”

Through this, the pressure of the abundant glassy-winged sharpshooters can be reduced in the vineyard, allowing ease of organic viticulture. But it’s not as simple as a single solution.

Fischl is also replacing some of the front rows of vines with disease resistant stock and reinforces the “need to take multiple approaches.”

For something as complex as an ecosystem it will take plenty of steps to balance things out, but to rid the vineyard of a common pest there are two easy options: ladybugs and soldier beetles.

“We keep a fair amount of long grass in the vineyard and tend to mow just every second row during spring. The soldier beetle goes around doing wonderful things like eating aphids, and lives in long grass. So, if you want to attract them keep the grass long,” said Jonathan.

Before receiving an IPM consultation

Synthetic products

For those farming conventionally, but who wish to reduce their chemical footprint, combining an IPM plan with synthetic products as a last resort is a good way to insure against failure.

“If your goal is truly noble and environmental, and you want to keep resistance down etc. that’s great. I like these basic low spectrum materials when there’s low disease pressure.

“The curatives for powdery mildew are organic which is great, but say sulphur isn’t working as a preventative and you need to use something synthetic.

“You can’t roll up a piece of paper and stick it in to your bottle saying ‘hey customer, sorry, we can’t make any wine this year because we had to stick to organics,’”

 

“You can’t roll up a piece of paper and stick it in to your bottle saying ‘hey customer, sorry, we can’t make any wine this year because we had to stick to organics,’” said Fischl. He adds that losing a certification can be damaging for a brand, but sometimes that means losing vines instead.

“We can do all of this stuff inside the vineyard like using cover crops and engineering the environment outside to make sure it’s happy, but under periods of high pressure there might be times when you need to use a synthetic chemical.”

“I’m using bugs. If I go out and spray I might get a few days out of an organic treatment, but my bugs are out there working all day every day.”

That said, there are times when a synthetic product is brought in, but care is taken to spray at the right times to maximise its effectiveness – like days with no/low rainfall and spraying at the very last minute to decrease resistance.

A labour of love

Of course, managing a vineyard in this way is more laborious than conventional farming methods, but in the long term it can be financially beneficial, as the cost of synthetic products is greatly reduced.

“One of the other downstream benefits is that many of the components of IPM are valuable for other biological functions,” said Fischl.

The vineyard orchard at Tarahill

That’s things like cover crops and using plants as hosts for useful insects. All of these practises add to the habitat through creating plant food, cycling phosphorous, building nitrogen, and organic matter in the soil.

“There’s always going to be maintenance, however after a few years our goal is for these systems to establish, and eventually they are designed to require less input than conventional management. We want the new cover crops to establish and self-seed.”

Luckily for Tarahill, the hard work has been done and the ecosystem is humming away in the background. Currently, their biggest issue (aside from slowly changing to phylloxera resistant rootstock) is wombats coming in from the creek.

“They dig and rip out plants in their path. If there’s something in the way they’ll just go right through it. They usually stick to the creek, but if you have a wombat digging through your vineyard you’ve got a problem.”

Fischl adds that plenty can be done outside the critical grape harvest period, so management during vintage isn’t often an issue. Plus, advertising an eco-friendly growing approach can add invaluable marketing and tourism leverage.

 

Daniel Fischl is an international viticultural advisor, and principle scientist at Eartrumpet Consulting. He can be reached at daniel@eartrumpet.com.au or on +61413765367

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