What Are Vineyards Made Of ?

What strikes you first when looking at a vineyard? Perhaps the vines themselves? Your eye may be caught by random scatterings of gnarly old bushes or by the military neatness of rows of trained vines, luxuriant in foliage in summer and little more than gaunt woody skeletons in winter. But possibly more striking might be the land itself—the geology, or at least manifestations of it. The vines may extend across a vast, flat plain, or they may be perched on a vertiginous slope, or anywhere in between—it depends on the bedrock geology. How well the vines grow will be influenced by how that bedrock weathers into soil and how the vine roots respond. The soil may have an eye-catching color or may be astonishingly stony, consisting of little more than rock debris. This quality, too, depends on the geology. But what exactly is this vineyard ground? What are such things as bedrock, soil, and stone made of? Where do they come from? How did they get this way? The answers form the basis of understanding vineyard geology, so let’s begin here, with a few fundamentals. We can think about what the ground in a vineyard is made of in three ways. The first way is that, like all matter, it consists of atoms of chemical elements. And remarkably, although there are nearly a hundred different chemical elements in nature, the ground is dominated by just eight of them (Figure 1.1a). You could even say that it’s pretty much made up of only four of these elements, as the first four on the list account for nearly 88% of the composition. Preponderant among them are oxygen, at no less than 46%, and silicon, at 28%. So there’s a lot of these two elements in most vineyards! As an aside, it’s the same kind of story with living organisms: about 95% of their composition consists of just three elements—carbon, oxygen, and hydrogen—and that includes grapevines and grapes (Figure 1.1b).