Ever wonder why you aren’t allowed to bring live plants to another country? The story of the phylloxera blight provides an excellent example of what can happen when non-native species are introduced in new settings.
In the mid 1800′s, the great vines of Europe were being destroyed. Most French vineyards were completely wiped out within 20 years. What caused this widespread devastation?
Phylloxera, a tiny root louse related to aphids, had taken a free ride across the ocean from the East Coast of the United States.
The vineyards of Europe had experienced a powdery mildew fungus to which East Coast vines seemed resistant.
As an experiment, vines were brought across the Atlantic to see how they would do in Europe. Unfortunately, the stowaway on board these vines was worse than the fungus.
When the French biologist Jules-Emile Planchon first postulated that Phylloxera was causing the blight, it took 4 years for Charles Valentine Riley, an American entomologist, to confirm his theory.
Vineyard owners tried many methods to control the insect. Irrigating the vines with white wine, chemical attacks, and even putting toads and chickens amongst the vines were all tried.
Flooding the vineyard for a short time in the winter was successful but most hillside vineyards were not able to do this successfully. Carbon bisulphide was also used to fight the louse.
Charles Valentine Riley noted that the native American vines were resistant and suggested grafting European vines (Vitis vinifera) onto American rootstocks (Vitis Labrusca).
The French government, which had offered a large reward for finding a solution to this economy wrecking problem awarded Riley the Cross of the Legion of Honor.
This solution was not without debate: would wines produced on American roots would be inferior to the previously great wines of Europe?
Ultimately, there was no choice but to go ahead. To rebuild the great vineyards of Europe, hundreds of thousands of roots were shipped from the United States, mainly from Missouri and Texas.
Phylloxera has spread throughout the world, causing crises and grafting where it has landed. Very few pre-phylloxera European bottles are known to exist in the world. Due to their scarcity, these come at a premium price and cause quite a stir at wine auctions when a bottle is put up for sale.
Phylloxera hit California in the 1980s, causing many vineyards to have to replant at a cost of over a billion dollars. In some ways, this helped the industry as vineyards gave more thought to the best grapes to plant for their plots and corrected other planting errors.
Where can you find pre-phylloxera vines that still happily exist? Chile, where vines were brought from Europe prior to the infestation.