The surface layer of soil developed in the normal soil-forming process, that is, the accumulation layer, it is often called the fertile layer. Its value for the cultivation of plants is always high, though it may vary within fairly considerable limits. It depends on its thickness, organic material content and overall fertility. It is impossible to artificially recreate the fertile layer, and it is always very costly to create different substrates with similar values ​​in its place. Therefore, it is obligatory to protect and protect this layer in the area of ​​earthworks and construction works. There are special regulations in this respect obliging to protect fertile land by collecting and storing.

The thickness of the fertile layer varies and ranges from 10-30 cm. Certain types of soil, like for example. peat soils, may have a much greater thickness of the layer to be protected, depending on the thickness of the peat seam.

Securing the fertile layer in places not affected by height changes is to prevent its contamination with other materials, soil from deeper layers and excessive compacting destroying its structure. Therefore, in places not covered by earthworks, it is often necessary to remove this layer for a certain period. After removal, the soil is stored in piles, the height of which should not exceed 1,5 m, and the width 2-4 m. upper, the surface of the prism should be slightly concave, which ensures better absorption of rainwater. Long-term storage in large heaps causes the processes of anaerobic decomposition of organic matter that reduce the value of the land.