Subsistence farming and Undersoil

Subsistence farming noun - Farming that provides for the basic needs of the farmer without surpluses for marketing.

Undersoil and subsistence farming are semantically related. in farming for basic needs topic. In some cases you can use "Undersoil" instead a noun phrase "Subsistence farming".

Undersoil noun - The layer of soil between the topsoil and bedrock.

Subsistence farming and undersoil are semantically related. Sometimes you can replace phrase "Subsistence farming" with "Undersoil", this terms are similar.