🦠 Phylloxera

Phylloxera is a tiny aphid that feeds on grapevine roots. It comes from America. In the 19th century it was accidentally brought to Europe and destroyed a huge number of vineyards. This crisis is known as the Great French Wine Blight.

The European vine, Vitis vinifera, cannot defend itself against this insect. Its roots are weak, and the vine sickens and dies. American species have more resistant roots. What saved viticulture was grafting: European vines were grafted onto American rootstocks and grow on roots that the insect does not destroy. The varieties were kept, but the roots became different.

Phylloxera lives poorly in sand, so ungrafted vines survived on sandy soils. The insect is still one of the main grape pests. Its story changed the world of wine: after it, vineyards had to be replanted. Today most vines in the world grow on grafted roots.