Soils

LOESS LOAM AND QUARTZITE

LOESS LOAM AND QUARTZITE

Bischofsberg, Klosterlay, Magdalenenkreuz

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Ice age dust is found in most of yineyard soils. Storm winds moved these fine dust particles from ancient gravel beds deposited by wide rivers. The dust dropped out of the wine in shielded locations accumulating to thick loess beds. The fragile substrate makes it easy for roots to penetrate deep into the soil and reach water and nutrients. The most important property of the loess is its high available soil water capacity. The silty soil is easy to manage but is also readily washed away. The sandy loess is partially mixed with gravel sediments of the former terrace banks of the Rhine, with quartzite or slate or coarse coastal sediments from the Tertiary.

QUARTZ AND QUARTZITE

QUARTZ AND QUARTZITE

BERG ROSENECK

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Summits of the Taunus mountain range consists of a hard rock called quartzite. The sandy sediments washed out of long gone mountain ranges were deposited near a coast during the Lover Denovian (about 400 million years ago). These deposits were soon compacted to form sandstone, which was subjected to high pressures when it became buried beneath thick layers of rocks. This resulted in a modification of the crystalline structure of the sandstone turning it into a hard quartzite and finally to Taunus mountains. The Taunus quartzite contains more than 90% quartz (SiO2) and very little impurities. Therefore, the rock has a very low carbonate and iron oxide content. The mineral nutrient content is low. The weathering processes of quartzite and slate results in solid white quartzite blocks. They are particularly wheather resistant and therefore accumulate the soil.

GREY SLATE

GREY SLATE

BERG ROTTLAND

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Slates are debris soils where the landscape is dominated by a grey color of the weathered grey-blue Hunsrueck slates. Dark-brown humus rich topsoil is often covered by slate debris and rubble which protects the soil from desiccation. The spaces between the loose materials are therefore well aerated. It is possible to feel loess as well as clay and mineral-rich fine earth derived from weathered slate. The vines are well supplied with minerals such as potassium, magnesium, sodium and iron from the clay fraction. Slate weathers rapidly thus ensuring a continuous supply of nutrients and mirco-nutrients.

RED SLATE WITH QUARTZITE

RED SLATE WITH QUARTZITE

BERG KAISERSTEINFELS & BERG SCHLOSSBERG

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Here , the soil contains a combination of red clay slate with mixed-in quartzite. The red slates are soft water sediments. Red coloring is a result of the iron content of these slates that have been oxidized to iron oxide under an arid climate, leaving a very rocky, hard soil. It has less minerals than the rich soils of grey slate but still much more than the quartzite soils. The remaining thin layer of soil is very stony and can only store a limited amount of water. In addition to this, the dense, clay subsoil is very difficult for roots to penetrate, creating demanding conditions for grapevines. The soil is quick to warm because of the low water content and high solar radiation levels along the slope. As a result, the vine experiences water stress early in the year and must somehow cope with the available water. The plants react by reducing the number and size of the grapes. Therefore, these sites produce low yields of very aromatic grapes.