Changes

* <span style="color:#FFFFFF; background:#8B4513">'''White'''</span> or <span style="color:#808080">'''grey'''</span> horizons between the topsoil and a clay subsoil can result from a long process of leaching. These horizons are washed out and usually have less clay than the darker topsoil and are often sandy loams with a very high proportion of fine sand. Sand in these horizons is often over 70 % of the total mineral matter. The leaching occurs laterally, i.e. instead of water moving downwards through the soil it follows a path parallel to the ground surface and the upper surface of the subsoil. They invariably become saturated rapidly in winter and contribute to waterlogging. They are very rarely saline being so highly leached.

* <span style="color:#FFFFFF; background:#8B4513">'''White'''</span> or <span style="color:#808080">'''grey'''</span> horizons between the topsoil and a clay subsoil can result from a long process of leaching. These horizons are washed out and usually have less clay than the darker topsoil and are often sandy loams with a very high proportion of fine sand. Sand in these horizons is often over 70 % of the total mineral matter. The leaching occurs laterally, i.e. instead of water moving downwards through the soil it follows a path parallel to the ground surface and the upper surface of the subsoil. They invariably become saturated rapidly in winter and contribute to waterlogging. They are very rarely saline being so highly leached.

* White colours in the subsoil are often due to the presence of calcium carbonate. This can be tested for using a little hydrochloric acid. If carbonate is present a few drops of acid will cause the soil to fizz and bubble as carbon dioxide is formed by the reaction of acid and carbonate. The depth from the ground surface to such a layer is often a good indication of the amount of leaching that has occurred throughout the formation of the soil.

* <span style="color:#FFFFFF; background:#8B4513">'''White'''</span> colours in the subsoil are often due to the presence of calcium carbonate. This can be tested for using a little hydrochloric acid. If carbonate is present a few drops of acid will cause the soil to fizz and bubble as carbon dioxide is formed by the reaction of acid and carbonate. The depth from the ground surface to such a layer is often a good indication of the amount of leaching that has occurred throughout the formation of the soil.