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Soil scientists used to speak of soil quality, a concept expressing a soil’s “fitness for purpose.” The prime purpose was for agriculture and the production of food and fiber. However, to the general public soil quality is a rather abstract con­cept and in recent years the term has been replaced by soil health. A significant reason for this change is that health is a concept that resonates with people in a personal sense. This change is epitomized in the motto “healthy soil = healthy food = healthy people” on the website of the Rodale Institute in Pennsylvania (http://rodaleinstitute.org/). One consequence of this change is an increasing focus on the state of the soil’s biology, or life in the soil, an emphasis that is expressed through the promotion of organic and biodynamic systems of farming. Viticulture and winemaking are at the forefront of this trend. For example, Jane Wilson (2008), a vigneron in the Mudgee region of New South Wales, is quoted as saying, “the only way to build soil and release a lot of the available minerals is by looking after the biology,” and Steve Wratten (2009), professor of ecology at Lincoln University in New Zealand has said, “Organic viticulture rocks! It’s the future, it really is.” This exuberance has been taken up by Organic Winegrowers New Zealand, founded only in 2007, who have set a goal of “20 by 2020,” that is, 20% of the country’s vineyards under certified organic management by the year 2020. The Cornell Soil Health Assessment provides a more balanced assessment of soil health (Gugino et al., 2009). The underlying concept is that soil health is an integral expression of a soil’s chemical, physical, and biological attributes, which determine how well a soil provides various ecosystem functions, including nutrient cycling, supporting biodiversity, storing and filtering water, and maintaining resilience in the face of disturbance, both natural and anthropogenic. Although originally developed for crop land in the northeast United States, the Cornell soil health approach is readily adapted to viticulture, as explained by Schindelbeck and van Es (2011), and which is currently being attempted in Australia (Oliver et al., 2013; Riches et al., 2013).

As outlined in chapter 1, “determining the site” in old established wine regions such as Burgundy, Tuscany, and the Rheingau has been achieved through centuries of acquired knowledge of the interaction between climate, soil, and grape variety. Commonly, vines were planted on the shallow soils of steep slopes, leaving the more productive lower terraces and flood plains for the cultivation of cereal crops and other food staples, as shown, for example, by the vineyards along the Rhine River in Germany. The small vineyard blocks of the Rhine River, the Côte d’Or, Valais and Vaud regions of Switzerland allowed winegrowers to dif­ferentiate sites on the basis of the most favorable combination of local climate and soil, which underpinned the concept of terroir. In much of the New World, by contrast, where agricultural land was abundant and population pressure less, vineyards have been established on the better soils of the plains and river valleys, as exemplified by such regions as the Central Valley of California, the Riverina in New South Wales, Australia, and Marlborough in New Zealand. Apart from the availability of land, the overriding factor governing site selection was climate and the suitability of particular varieties to the prevailing regional climate. In such regions, although soil variability undoubtedly occurred, plantings of a single variety were made on large areas and vineyard blocks managed as one unit. Soil type and soil variability were largely ignored. Notwithstanding this approach to viticulture in New World countries, in recent time winegrowers aiming at the premium end of the market have become more focused on matching grape varieties to soil and climate and adopting winemaking techniques to attain specific outcomes for their products. For established vineyards, one obvious result of this change is the appearance of “single vineyard” wines that are promoted as expressing the sense of place or terroir. Another reflection of this attitudinal change is the application of precision viticulture (see “Managing Natural Soil Variability in a Vineyard,” chapter 6), whereby vineyard management and harvesting are tailored to the variable expression of soil and local climate in the yield and sensory characteristics of the fruit and wine.