In the 1860s through the 1870s, the French wine industry was in deep trouble. Somehow American plant lice had been transported to Europe and would eventually destroy around 40% of all French vineyards.
The entire French economy was hit hard and losses were in the billions. Ironically, the best solution was to import American rootstock and vines because they were immune to these specific type of plant lice. It worked and the industry recovered.
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Photo Credits / Sources:
By Colin (Flickr: the brat pack) [CC BY 2.0 (http://creativecommons.org/licenses/by/2.0)], via Wikimedia Commons