definition of loam types
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, boulder loam, loess loam, and mountain loam.
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.