Blended wines are not considered inferior to veritable wines rather they are different style of wine making some of the world's most highly regarded wines from regions like Bordeaux and the Rhone Valley are blended from different grape varieties wine can also be made from other species of grapes or from hybrids created by genetically crossing two species v. Labrusca of which the Concord grape is a cultivar v. Aestivalis v. Ruprestris v. Rotundifolia and v. Riparian are native North American groups usually grown to eat fresh are for grape juice jam or jelly and only occasionally made into wine.
Hybridization is different from grafting most of the world's vineyards are planted with European v. Vinifera vines that have been grafted onto North American species rootstock a common practice due to their resistance to phylloxera a root louse that eventually kills the vine.
In the late 19th century most Europe's vineyards excluding some of the driest in the south we're devastated by the infestation leading to widespread find us and eventually replanting. Grafting is done in every wine producing region in the world except Argentina the Canary Islands in Chile the only place is not yet exposed to the insect.
In the context of wine production terroir is a concept that encompasses the varieties of grapes used elevation and shape of the vineyard type and chemistry of the soil climate and seasonal conditions and the local yeast cultures. The range of possible combinations from these factors can result in great differences among the wines influencing the fermentation finishing an aging process as well.
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