The Odenwald Wine Island is an outstanding location within the terroir of Hesse. The site is characterised by a felsic parent rock and an exceptional soil water regime typified by very high annual rainfall and a very dense subsoil.
     The subsoil consists of a red silty clay derived from the rhyolite. In the subtropical climate of the Tertiary period the rhyolite weathered to a fine-grained substrate (saprolite). This clay rich subsoil is very dense and therefore impedes root growth and water infiltration. This is a cool, fresh location, which may become waterlogged in spring. The soil is acid, which means that only a fraction of the mineral nutrient potential is available to plants. The plough horizon consists of the saprolite as well as added residual loess. The loess fraction improves the soil water conditions, aeration, nutrient content and the thermal properties, and also increases the rootability of the soil. The topsoil contains humus, which also improves soil structure. The location provides good conditions for slow and intensive grape ripening if an adequate nutrient supply is maintained.

THE ROCK
Magma that cools deep in the Earth’s crust does so very slowly, giving minerals time to form large crystals. When a volcano erupts, magma reaches the earth’s surface and cools rapidly, forming tiny crystals. A mixture between small and large crystals is called a porphyric structure. The mineral content of the rhyolite shows that this rock is the volcanic equivalent of the plutonic granite. Rhyolite is mainly composed of quartz and has a low nutrient content.
     Loess is a wind-deposited, fine-grained, calcareous sediment. Loess was formed in the periglacial dry climate of the Pleistocene ice ages. Under today’s climatic conditions, the calcium carbonate is leached by percolating rainwater, leaving a silty clay. The light coloured loess turns brown as a thin covering of oxidised