Silver-white shiny, medium-soft metal (Fe = ferrum), which is the fourth most abundant element of the earth's crust with just under 5% share. In the soil it occurs only very rarely dignified, but mostly in bound form sulfidischer and oxidic iron minerals. These include magnetic ironstone, red iron stone, brown iron stone and spade ironstone. In many soils iron is present in larger quantities. The common iron oxides give floors the characteristic reddish color. Such soil types are used in viticulture as Rotliegendes (Rotliegend) or Terra Rossa designated. Among other things, the Australian wine region draws Coonawarra such a type of soil. Also the single location Scharlachberg in Rheinhessen got its name because of the color.
All vertebrate organisms require iron as part of hemoglobin (red blood cell colorant). In plant growth, iron favors the photosynthesis the chlorophyll formation, without being incorporated, and of protein and nucleic acid. Iron is essential nutrient for the healthy Rebstock growth, Excessive levels of calcium. copper and phosphorus in the soil, as well as cool ground temperatures in connection with wetness have a negative effect on the iron metabolism. The iron can not be absorbed by the roots in this case. This leads to acute chlorophyll deficiency and yellowish discoloration of the leaves or. chlorosis (Iron deficiency or bad weather chlorosis). In extreme cases it comes to Verrieseln the bills and even the death of the vine. A fertilization must be in the form of organic compounds (gel). Also by contact with Corridors in the basement at the winemaking too much iron can get into the wine, which is caused by cloudiness and metallic - bitter Taste and the wine error Black break manifests. The Perceptual threshold is about 10 mg / l.