What is another word for under soils?
Pronunciation: [ˌʌndə sˈɔ͡ɪlz] (IPA) 
Under soils can be referred to as subsoil, lower soil layers, subterranean soil, underground soil, or below-ground soil. Subsoil is the layer of soil that lies immediately below the topsoil and is characterized by a lower organic content and denser texture. Lower soil layers refer to the layers of soil that are situated below the surface soil. Subterranean soil is located beneath the ground surface where the roots of plants and trees grow. Underground soil pertains to the soil that is situated underneath the earth's surface and can be inaccessible to the naked eye. Lastly, below-ground soil refers to any soil that is situated below the surface level.
