In a work on soil variability within a given site, a detailed study was undertaken to determine the perturbation on soil horizons by a windfall. A representative windfall of the most frequent type was studied. The arrangement of soil horizons was described for this type of windfall qualified as normal. The mechanisms of this new arrangement of soil horizons are also described. Other types of windfall are briefly described and compared with the normal one. The importance of this phenomenon is discussed in view of the variations in soil properties between (bordering) profiles and its effect to soil development in a given ecosystem.