On the example of soils of the Basic Experimental Complex of the Institute of Atmospheric Optics, Siberian Branch of the Russian Academy of Sciences (Tomsk), the influence of spring grass burns on the properties of the upper layer of the humus horizon of Chernozems. In the areas that burned two months ago, 1, 2, 3 and 11 years ago, a total of 56 samples (5–9 replicates) were collected. We found a considerably high stability of the controlled properties of soils (cationic-anionic composition of water extract, content of grain-size fractions and mobile compounds of a wide range of elements, total C and N, organic carbon, pH value, basicity from carbonates) to pyrogenic effects from spring grass fires. Informative indicators reflecting a significant pyrogenic impact over the past 11 years were the content of mobile Ca, Mg and Sr, as well as water-soluble Mg2+ and basicity from carbonates. Their content is higher in the soils of young (0–3 years) burnt areas relative to the old (11 year old) burnt areas and unburnt areas. Among the studied parameters, the pH value, the content of mobile Ba and Sr, and grain-size fractions of 1–5, 5–10, and 10–50 µm, had the low coefficient of variation (20%), and content of water-soluble ammonium and mobile Li and Zn had the high coefficient of variation (70%).