In the 1860s, French vine-growers began to notice their vineyards mysteriously dying. Healthy vines would weaken, their leaves yellowing, and within two or three years they were dead, the decline spreading outward across the countryside in expanding rings of ruin. Dig up a dying vine and the roots would be swollen, rotten and covered in strange galls, but no one could find the cause. It took years to identify the culprit, and when they did it was almost too small to see: a yellowish, aphid-like insect no bigger than a pinhead, feeding on the roots. It had crossed the Atlantic from America, and it would go on to destroy the greater part of Europe's vineyards in one of the worst agricultural catastrophes in history.
The great blight
The insect was phylloxera, a tiny sap-sucking louse native to the eastern United States. American wild vines had evolved alongside it over millennia and had developed resistance; their roots could tolerate the insect's feeding. The European wine grape, Vitis vinifera — the species behind virtually all fine wine, from Bordeaux to Burgundy to the vineyards of Germany, Spain and Italy — had no such defence. When phylloxera arrived, almost certainly carried on American vine cuttings imported by curious botanists in an age of enthusiastic plant collecting, it found an entire continent of defenceless roots.
The result was devastation on a scale that is hard to overstate. From its first appearance in the south of France, the infestation spread relentlessly through the 1860s, 1870s and 1880s, killing vines across France and then across most of the European wine-growing world. Enormous swathes of vineyard — a very large fraction of the French total — were destroyed. Livelihoods collapsed, rural regions were plunged into crisis, and for a time it seemed genuinely possible that European wine as the world knew it might cease to exist. The French government offered a large prize for a solution, and desperate growers tried everything: flooding their vineyards, burying live toads beneath the vines, and dosing the soil with the toxic chemical carbon disulphide, which worked after a fashion but was expensive and dangerous.
The American cure
The solution, when it came, was beautifully paradoxical: if American roots were resistant to an American pest, then European vines should be grown on American roots. The technique was grafting — taking a cutting of the European Vitis vinifera vine, prized for the quality of its fruit, and joining it onto the rootstock of a resistant American vine species. The American roots, immune to the louse, kept the plant alive; the European upper vine, or scion, went on producing the familiar noble grapes. The insight is credited to a group of researchers and growers including the botanist Jules Émile Planchon, who had helped identify the insect, working in cooperation with American entomologists such as Charles Valentine Riley, who understood the pest from its home ground.
Grafting was laborious and controversial, but it worked, and over the following decades the vineyards of Europe were painstakingly replanted, vine by grafted vine, on American roots. Almost every European wine vine in the world today — and most vines everywhere the louse has reached — grows on an American rootstock as a direct legacy of this reconstruction. The wine survived because it was, quite literally, given new foundations.
The purists' quarrel
The grafting solution left behind a debate that has never entirely died. Some traditionalists insist that the flavour of wine changed with the switch to grafted vines — that pre-phylloxera wines, grown on their own European roots, possessed a depth or purity that was lost. It is an argument impossible to settle, since almost no ungrafted old-vine wine survives to compare, and it shades easily into romantic myth. A handful of vineyards escaped the plague and remain ungrafted to this day, protected by geography: phylloxera struggles to move through pure sandy soils, so vines planted in sand survived, and entire wine regions such as Chile, isolated by ocean, desert and mountains, remained free of the louse and grow ungrafted vines still. Enthusiasts prize the rare wines from these survivors, though whether the difference they taste is the rootstock or their own expectations is anyone's guess.
What is beyond dispute is the scale of what nearly happened. A creature smaller than a grain of rice, carried across an ocean by accident, came within reach of destroying one of civilisation's oldest pleasures, and the cure required Europe to graft its most cherished vines onto the roots of the very continent that had sent the plague. Every glass of European wine drunk today rests, unseen and underground, on an American foundation — a permanent reminder of the summer the vineyards began to die and the strange, humbling remedy that saved them.
Quiz nuggets
- Phylloxera is a tiny aphid-like insect native to North America that attacks grapevine roots.
- Introduced on American vine cuttings, it destroyed a large fraction of Europe's vineyards from the 1860s onward in the "Great French Wine Blight."
- The cure was grafting European Vitis vinifera vines onto resistant American rootstock.
- Almost all European wine vines today grow on American rootstock as a result.
- Sandy soils and isolated regions such as Chile escaped phylloxera, and still grow ungrafted vines.