The steepness of vineyards is given in percent (%) or degrees (°). However, the values given in many sources are often incorrect due to misrepresentation or confusion between percent and degree. At 45°, this is converted to 100%; in contrast, 45% is only 24°. The not possible 100° (overhang) would result in 567% purely mathematically. A slope of 90° corresponds to a vertical wall. The real maximum values of vineyards are about 75° (373%); the 68° of the single vineyard Calmont in Bremm on the Moselle come very close to this limit (see picture below). In steep-slope viticulture on extremely steep slopes, conventional mechanical cultivation is often not possible, but only laborious manual work with the help of special equipment. The vineyards there are usually laid out in terraces with retaining walls and stairs. Rope hoists or special caterpillar vehicles have to be used for the largely manual vineyard maintenance. For this reason, traditional cultivation systems such as single-pole training (Moselle pole cultivation) are often used. In exposed areas, the spraying of pesticides is carried out with the use of helicopters, and the transport of materials, people and grapes during the harvest is carried out via monorack railways.
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Diplom-Sommelier, Weinakademiker und Weinberater, Volders (Österreich)