Viticulture and Grapes

In producing wine, there's a perceived tension between what occurs "naturally" and what results from human intervention. Broadly, the debate is between the role of nature (environment and grape variety), and what the viticulturist and winemaker can do. In practice, this is a false dichotomy. For a commercial wine that is made on a large scale and sells for less than US $8, the essential element is the ability of the winemaker to maximize the character of the variety. For expensive, high-quality wines the varietal character should shine through, but the winemaker may also need enough restraint to reveal the environmental influences. In examining how wine is made, it becomes apparent that the relative importance of these factors will vary from wine to wine.

THE ENVIRONMENT FOR GROWING GRAPES
Vines need a temperate climate and generally flourish best between 30 and 50 degrees of latitude in the northern hemisphere and between 30 and 40 degrees in the southern hemisphere (because of its greater maritime influence). Altitude reduces the the average temperture by 2°F (0.6°C) for each 330 feet (100 in), so vines tend to be planted at lower levels except in the warmest climates. Vines must also have access either to a reasonable rainfall, ideally concentrated in winter, or irrigation.

Before examining the various natural conditions that affect vines, it is useful to examine the concept of terroir. This French term, related to terre, the word for soil, is more correctly translated as "region." The term encompasses the entire natural environment of the vine-the climate, soil, site and topography of the vineyard where it grows. It is a useful concept for some wines, but it also provokes much meaningless debate. Diehard terroiristes, usually perceived to be extreme Europhiles, claim that wine must reflect the specific site on which the grapes are grown. Their opponents, crudely caricatured as technocrats, retort that all you need to grow wine grapes is a decent warm climate and a regular supply of water (from irrigation, if necessary).

Whatever the merits of either argument, the reality is that most winemakers don't limit their production to grapes from single regions. At the end of the 1990s, even in France-the bastion of terroir based wines-50 percent of all wine sold was vin de table, which is not marketable under a region of origin. However, in California and the Southern Hemisphere, many wine producers continue to claim that the specific topographies and soils which characterize their own particular vineyards make their wines distinctive.

The average bottle of wine is sold for US $6 per bottle. At that price, it is enough to know that it comes from Languedoc or southeast Australia. There is no doubt that at the top end of the market-perhaps 1 percent of all wine sold-the specific site does influence the wine, modifying structure slightly and adding nuances of flavor. It is also true that some of the greatest wines are sold with only the broadest connection to a specific terroir-vintage port, champagne and Penfolds' Grange