Loam is a type of soil, consisting of sand, silt, and clay.
It occurs in various compositions under the upper humus layer,
in all parts of the world. Depending on their grain size
and their formation, there exist different types of loam:
Alluvial Loam
definition of loam types
Alluvial loam, also known as high tide loam, is characterized by its fluvial-morphological formation process. So, flowing water constantly transformed the muddy loose rock. Subsequently, the fine sediments subsided and alluvial loam arose. It is a yellowish, very clayey loam consisting of very small grains which have been rounded by the water.
Boulder Loam
definition of loam types
Boulder loam is glacial, fine-grained, non-layered sediment, which is partly interspersed with large rocks, so-called boulders. It was formed when moraines (of ice-age glaciers) were deposited. Depending on the degree of weathering and lime content, its color varies from grey to yellow-brown. Characteristic for this type of loam are the polished, round boulders, that are, fragments of magmatic or metamorphic rock of the Scandinavian mountains.
Loess Loam
definition of loam types
Loess is sediment shifted by the wind. The dust originates from glacially weathered moraine debris - so it is very, very old. Through various soil-forming processes, the sediment got decalcified, the mineral sub- stance weathered, and new clay minerals were formed. The result is a reddish or yellow- ochre colored, fine-grained loess loam. Compared to other types of loam, loess loam is very poor of clay, which makes it a little less plastic.
Mountain Loam
definition of loam types
Mountain loam is a type of soil that is found near the rocks from which it was formed. Quite in contrast to the other types of loam, which are carried to another place either by wind or water, mountain loam arose through weathering of its mother rock. It is fine-grained, non-layered sediment which is partly interspersed with larger, still very angular rocks. Its color depends on the source rock and can even be greenish, but is usually brown.
This whole process did not happen overnight.
Loam is the result of thousands of years of development.