Attack of the Phylloxera

No history of wine and vines can possibly omit the story of phylloxera.

Over the years, on my many travels among vineyards, time and again I’ve started a visit by looking at the very bottom of the young vines. And on these, beneath a protective waxy later, you can clearly see where the roots of an American vine have been grafted to a European one. The latter is known as Vitis vinifera for the quantities of wine that can be made from it. In showing its shoots, it allows winemakers to practice modern methods of vine cultivation, methods which date back to the advent of the phylloxera invasion.

Phylloxera is an insect native to North America, where it lives in symbiosis with American grapevines, which over time have developed a resistance to the insect. They can live with it; it doesn’t do them any great harm. Vitis vinifera, on the other hand, is not able to survive hosting the parasite, which attacks its roots, does tremendous damage, and opens the door to infections and funguses. Within two or three years, the plant is dead.

It was the nineteenth-century intensification of trade and movement between Europe and America that allowed this little parasite to settle in the Old World. In the mid-1800s it started to blight the work of winemakers in France, some of whom were experimenting and did not realize what they were about to unleash. Soon, the parasite had spread like wildfire across the continent. Vines started to die as winemakers flailed around for a way to contain the disease. They tried flooding the vines in order to drown the insect in sand, because they had noticed that it was far less prevalent and virulent in the sandier vineyards, especially those near the sea. Some were even driven to migration, opting to move their vineyards further south. But nothing proved effective in halting phylloxera’s advance. Rapidly, inexorably, it spread throughout Europe, ravaging it all. Winemakers began to wonder if the wound would be fatal, and whether Vitis vinifera and its wine might disappear off the face of the planet.

For a real solution, winemakers had to wait about thirty years from the opening of the “epidemic”. This arrived when American vine species were found to have immunity to the parasite. Some winemakers leapt on this immediately, and started growing American vines in their vineyards, but the resulting wines were really not a patch on those that Vitis vinifera could produce. But at some point, someone realized that the roots of the American vines could be grafted to the reproductive parts of the European ones. Phylloxera no longer posed a threat to the roots, which meant that the vines could bring forth their fruits as they always had done. 

The grafting technique made it possible to rebuild whole swathes of vineyards that had been decimated by the insect. But things could never be as they once had been: thousands of indigenous varieties of Vitis vinifera, mainstays of the ancient, medieval and early modern worlds, had been brought to their knees; others had been wiped out completely.

Over the decades, grafting has become the go-to technique in vine cultivation and wine production. It has been honed to a point at which it can be adapted to specific vines and to the types of soil they grow in. Grafting is therefore no longer solely a method of keeping down the phylloxera, which it rendered more or less irrelevant. Now, it is more a way of getting an agricultural advantage by making a plant that is as well-suited as possible to the environment in which it grows.

There are still parts of the world where phylloxera has never arrived or, if it has, has never managed to get a foothold. In these areas, you can find species of Vitis vinifera that are not grafted, which still preserve their original roots. The two most famous examples of this can be found in Chile and in certain parts of Australia, where strict controls on imported plants have staved off the threat of phylloxera. In Italy, too, there are a few little havens where viticulture can be practised without the need for grafting, normally where the terroir is sandy or at high altitudes, where the insect can’t survive. The vineyards on the slopes of Mount Etna, for instance, and certain tracts of the Val d’Aosta or Sulcis in Sardinia.

Writing this brief history, one realizes just how vital human intervention is and has been to the continued production of wine. Procedures such as grafting, pruning, and even the harvest: there’s nothing natural about them, but we can’t do without them in the winemaking world. But we will continue to enjoy the fruits of our labors, the fruits of the vines, only if we continue to work in a way that shows nature all the respect it deserves.