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The participation of soil iron in the formation of physics‐chemical features in feed of plants and microorganisms is well known. Because of the active role of Fe in soil landscapes the Fe state is taken into account in investigations of the genesis of soils. In spite of a relatively high content of iron in soils up to 40%–45% (relative to Fe) its numerical forms are diagnosed in a complex way by Ronthgen diffractometry, differential thermal analysis, and microscopy. Thus, chemical extracts are widely used in soil science. Extracted Fe is considered to be of amorphous, strong or weak crystallized forms. These gradations are of wide use but they are not correct. This is established by some authors by means of magnetic measurements and Mössbauer spectroscopy [Jeanory et al., Sci. Solids 135 (1986)] before and after magnetic separation and chemical extracts [Fine and Singer, Soil Sci. Soc. Am. J. 53, 191 (1989)]. We used the measurements of magnetic susceptibility and saturation and nuclear gamma resonance for the usual soils and electron paramagnetic resonance for weak magnetic Fe containing minerals (before the extract). Our results are comparable with the above research and lead to the next conclusions: (1) ordered alternations of magnetic parameters and results of action of extracts are absent; (2) the Mehra–Jackson extract (sometimes the Tamm’s extract) often extracts the crystallized magneticordered and paramagnetic silicate and superparamagnetic forms of Fe; (3) magnetic susceptibility and magnetic saturation increase in some types of soils (brown earth, ferralsol, alluvial soil) at dissolution of the alumosilicate part of soils because of enrichment by chemically strong particles of magnetite; (4) the conclusions on extracts (as far as crystallized silicate amorphous forms) do not have generalized characteristics.