Hardpan

The term refers to a hardpan soil horizon in the subsoil of podzol. The deposition of eroded in the Ae horizon of the surface soil humus and iron compounds results in a cemented, sandy, firm illuvial horizon. Hardpan consists of a brown-black Bh horizon with predominant humus accumulation and an underlying russet Bs horizon with accumulation of sesquioxides that are common to only 10 to 20 cm thick and have a conspicuous mottling. Since hardpan is almost impervious to water and can hardly be penetrated by the roots, the vegetation is severely impaired.

By deep plowing the Ortsteinschicht can be broken up and the land be brought under cultivation.