AxR1 is a grape rootstock once widely used in California viticulture. Its name is an abbreviation for "Aramon Rupestris Ganzin No. 1", which in turn is based on its parentage: a cross (made by a French grape hybridizer named Ganzin) between Aramon, a Vitis vinifera cultivar, and Rupestris, an American grape species, Vitis rupestris - also used on its own as rootstock, "Rupestris St. George" or "St. George," referring to a town in the South of France, Saint Georges d'Orques, where it was popular.
It achieved a degree of notoriety in California when, after decades of recommendation as a preferred rootstock - despite repeated warnings from France and South Africa about its susceptibility (it had failed in Europe in the early 1900s), it ultimately succumbed to phylloxera in the 1980s, requiring the replanting of most of Napa and Sonoma, with disastrous financial consequences.
Most current day grape rootstocks were and are originally imported from Texas. These were taken from the native wild mustang grapes that grow across Texas. This rootstock also saved France's grape industry in the early 1900s when phylloxera decimated the wine and vineyards of Europe.
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