THE SLOPES OF THE EASTERN RHEINGAU near to the Taunus are covered with phyllite debris mixed with residual loess. The fraction of coarse material is high. These are dry, mineral-rich soils. The weathering of the phyllite ensures a steady supply with mineral nutrients.
      The root density of the fertile topsoil is very high and the dark colour is due to the humus content. The loamy soil consists of residual loess mixed with clay, which originates from the weathering of the phyllite. Weathered iron minerals give the soil its brown colour. The soil density and the coarse material fraction (rubble, stones) increase with depth. The strongly weathered phyllite is found beneath a light brown layer of Pleistocene drift.
      The phyllite debris soils are thin, leaving plants little space to spread out their roots. Furthermore these soils also have a high coarse material fraction. These two factors result in a dry soil, capable of only storing limited amounts of plant available water. These higher locations are nominally cooler and moister than those lower down in the Rheingau. However, they are quick to warm and air can circulate easily between the coarse constituents. This promotes vine growth resulting in excellent grape ripening conditions.