How Do Winegrowers Prevent Phylloxera?

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At some point during the wine-loving journey of everyone you will encounter mysterious references to the phylloxera. What is it , and what is the significant?

Phylloxera is an insect that resembles an aphid (a louse) which feeds on grapevine roots, which kills the grapevine. The pest moved across Eastern North America to Europe and destroyed vineyards by the latter part of the 1800s. The only way to prevent it is to graft resistant to phylloxera American vine rootstocks to European vines (aka Vitis Vinifera – e.g., Merlot, Chardonnay and so on.). Although we have known about the prevention for more than 100 years, it was known that phylloxera was a major problem for growers of grapes in California in the 1980s.

Grapevine Phylloxera: The Devastatrix

Phylloxera (pronounced the sound of fell-OXera) is tiny louse which goes through a long and intricate lifecycle on grapevines. It is a natural resident of the indigenous grapevines that grow in the eastern region of the North American continent, phylloxera and the specific vines grew over time in a synbiotic relationship.

Things became interesting in the early 1900s when botanists unknowingly transferred phylloxera to Europe, Australia, and even to the western US in the latter part of the 1800s. Sending exotic plants to share with friends and relatives was the trend at the time (Victorians are a good example ) And among the sea-born plants were the cuttings that were indigenous American grapevines.

Not only the vines completed the trip, but they also insects that stow away.

From garden plots and greenhouses within France, phylloxera marched across Europe throughout the 1900s and effectively destroyed the wine-growing industry. The Vitis vinifera, also known as European grapevine varieties, did not have the natural resistance to the phylloxera. Every single vine that was affected by phylloxera fell.

When France’s wine production declined and the wine-producing regions were rediscovered, other lesser-known regions rose to compete with France, bringing some unexpected results.

Paris :Librairie agricole de la maison rustique,1829-1974..

First, experienced French vineyard managers and viniculturalists relocated into areas that were not yet affected by the phylloxera. This had a positive net result, increasing the quality of local wine and improving winemaking knowledge in all areas where French workers migrated to make wine.

Additionally, the necessity in exporting highly skilled labourers and import wine to the thirsty population led to an increase in commercial and agricultural traffic across France and other wine-growing regions, which was made possible by newly constructed railroads. This has accelerated the spread of phylloxera into vineyards throughout Europe.

The result was that, by 1910, almost none of the European wine-producing region had remained unaffected.

A representation of a grapevine from the 1890s of the rootstock prior to and following an outbreak of phylloxera.

A representation of a grapevine from the 1890s of a rootstock, before and after an outbreak of phylloxera.

How can winegrowers prevent Phylloxera?

The only known method for treating phylloxera is root grafting.

Horticultural grafting has been practiced for many years. This easy procedure takes the phylloxera-resistant rootstocks (the root-stem at the bottom of a vine) from the native American vine species Vitis berlandieri, Vitis riparia or Vitis rupestris and connects it to the European fine-wine producing plant Vitis vinifera (the green leafy portion that grows on the vine).

Grafting has become the cure-all for damaged vineyards.

When phylloxera struck grapevines that were not yet planted in Europe in the beginning of the 1900s, the remedy was widely known. Grape growers swiftly grafted their vineyards and only lost some years of production.

Grafting today is an ever-changing science. Nurseries plant new vines using root grafts that incorporate drought resistance, phylloxera and even tolerance to salinity in the soil. Yay! Science!

The article from 1898 in the San Francisco newspaper announcement stating that the application of bacteria could help to treat the phylloxera. Before grafting was popular as a cure for phylloxera, and purportedly like snake oil. every salesperson had an answer.

A article from 1898 in the San Francisco newspaper announcement stated that a bacteria treatment could help to treat the phylloxera. Before grafting was popular and phylloxera cures claimed to be like snake oil. every salesperson offered an answer.

Are All Grapevines Are grafted?

There is no guarantee that all grapevines can be transplanted. Self-rooted vines, which are those that have never had grafts and that can thrive from their roots are rare, but sought-after by wine lovers. Some special circumstances enable this.
Special Sandy Soils.

Phylloxera isn’t a good choice for sandy soils that are deep and deep so the vineyards lucky enough to be in these soil types can be self-rooted.

Jargon Alert”Ow-rooted” is a way to state that the vine hasn’t been being grafted.

Geographically remote.

Certain grape-producing regions across the globe have not saw the pest being introduced.

Chile has the distinction of being the sole major global producer of grapes which has never experienced the phylloxera.

The Andean mountains to the west as well as The Atacama Desert to the north effectively separated the country from the over-land migration of insects. Today strict quarantine laws guard the Chilean wine industry.

Perhaps the most well-known stand-in against phylloxera are the vineyards in Barossa Valley, Australia which are still free of phylloxera, just 150 years after the bug landed on the continent. Older vines planted in 1890s have earned the label of being the oldest around the globe’ due to their free of phylloxera.

Nowadays, some winemakers decide to set up newer vineyards based on American rootstock to hedge their bets against the possibility of the arrival of phylloxera. Others believe in the tenacity of Barossa Valley’s long and storied background against the louse.
Is Phylloxera Still an Issue?

It is likely that known-prevention vignerons had said goodbye to their arch-nemesis aphid in the year 1910.

AXR1 AXR1, a infamous rootsstock hybrid that crossed V. vinifera with V. rupestris has gained a lot of attention throughout North America as a suitably resistant to phylloxera. The rootstock was not a success across Europe as well as South Africa, however, and despite the warnings issued to their viticultural relatives across the pond, seemed to show excellent outcomes in California. Thus, the vineyard owners planted AXR1 widely throughout Napa as well as Sonoma.

Unfortunately, AXR1’s vinifera parental lineage which is a tiny portion of vinifera’s DNA, proved disastrous for the vines. Even in the 1980s, owners of vineyards were forced to tear up their vineyards to replant them with fully resistant phylloxera rootstocks.

My vinous my dears, is a short overview of the phylloxera.