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Just Because You’re Paranoid Doesn’t Mean They’re Not Out to Get You

Viticulturists. The ones that WineDown knows are absolutely lovely, but how they manage to maintain their equanimity is a complete mystery. Something’s ALWAYS out to get them. OK, maybe not them, but their tender charges. It’s not just the implacable weather – there’s also the animal world. This thing called Nematode Attack would give even Stephen King the willies. Fight off the tiny parasitic worms, and the twin Mildews - Powdery and Downy may be lying in wait: their fluffily benign names belying the vicious nature of their attacks. Bunch Rot… Canker… Phomopsis… Mealybugs. Viticulturists learn to keep their friends close and their enemies even closer: it was a stroke of genius to befriend Botrytis Cinerea. 

But one name strikes fear into the heart of viticulturists everywhere: Phylloxera. 

The Devastator

Its scientific name is Daktulosphaira vitifoliae; the French - with a justifiable touch of histrionics - dubbed it PHYLLOXERA VASTATRIX from the Latin for ‘Devastator’. But it’s known throughout the world simply as Phylloxera – the louse that changed wine forever. 

Phylloxera is a tiny pale-yellow sap-sucking insect, related to aphids. It feeds on the roots and (sometimes) leaves of grapevines, creating deformities, cutting off the flow of water and nutrients, and leaving the vine vulnerable to secondary infections. An infestation of phylloxera is a vineyard death sentence: there is no treatment, no mitigation: Infected vines die within a few years. The only course of action is vine pull and burning.

Where did it come from?

Phylloxera is native to North America – specifically, the Mississippi Valley – where it feeds on the local Vitis Labrusca vines without impediment. But, sometime during the 1800s – in that thrilling post-industrial-revolution period when modern shipping brought Europe within weeks of the USA – Phylloxera hitched a ride with some Vitis Labrusca vines on a Steam Packet destined for France.

Unleashed

In 1866, a southern Rhône grower reported the death of a block of vines. It had taken two growing seasons for his healthy vineyard to wither and die. Forensic investigations showed only diseased and deformed roots; however neighbouring vines were teeming with tiny yellow insects. While scientists and government officials argued about the appropriate course of action, Phylloxera munched its way through the Vitis Vinifera vines of Languedoc, Provence, and Bordeaux. When the invaders looked set to take Champagne, the French government offered a reward to anyone finding a remedy. There was a slew of suggestions - many of which involved concoctions of garlic and urine. A curious odour descended over France, but no cure was found. There was, however, a breakthrough: The American Vitis Labrusca vines - which had carried phylloxera to Europe - were known to be resistant to the bug. Experiments with hybrids had only limited success but grafting Vinifera onto the resistant rootstock proved effective. The trick was convincing the French to do it.

Meanwhile…

As the battles raged, Phylloxera took a tour of Europe, decimating vineyards from Germany to Greece. By 1877 it had become Australia’s newest unwanted guest. It made itself at home in Geelong, before marching north to NSW, then on to Qld. Tassie and WA were spared the onslaught by dint of their isolation. 

With incredible foresight, South Australia had banned movement of vine material and machinery even before Phylloxera was identified in Australia. It was this decisive action that kept Phylloxera out of the state, and it’s the reason why SA is home today to some of the oldest vines in the world - still growing on their original European rootstocks.

Control

Perhaps because of our experiences with other biological invaders (Cane Toads, Prickly Pear, Leo Sayer), we Aussies take Phylloxera very seriously. Resistant rootstocks are the primary defence, backed by strict quarantine processes, and designated zoning: Phylloxera Exclusion Zones (PEZ), Phylloxera Risk Zones (PRZ), and Phylloxera Infected Zones (PIZ) – with a five-kilometre vine-free buffer surrounding any zone of infection. 

That should keep the little buggers quiet. Now, about Leo…