Soil is the name for the various kinds of ground that can be planted on (both above and below ground) without irrigation using water. In DF, the category of "Soil" includes all types of sand, clay, ooze and any "non-stone" layer equally, even if you or I generally don't associate that substance with "growing plants".
|Sandy clay loam|
|Silty clay loam|
- The "topsoil" types listed in the upper part of the table do not count as sand for glassmaking, even if their names include the word "sand" - only those in the "Sand" section at the bottom are usable for this purpose.
- The 3 "ocean floor" layers are only found under deep ocean tiles, usually far out from any embarkable site. Thus, they can rarely, if ever, be encountered in either fortress mode or adventurer mode.
- Soil layers marked with
≈are capable of supporting an aquifer.
- The "clay" types listed at the bottom can be used for making ceramic items. Fire clay produces stoneware, while the other types produce earthenware.
When starting a new fortress, types and quantities of available soils are listed at the bottom right of the fortress location selection screen. In contrast to rock types, soil type names appear in brown, and are usually closest to the top of the list, and thus, closest to the surface of the ground.
Digging into soil does not generate any byproduct materials, unlike digging in rock, and also is a much faster process which makes it much easier to create storerooms and other large areas of empty space, and to train miners.
Building a farm plot or road or removing a construction on top of soil will cause it to become "furrowed", making it appear with the
~ tiles. Furrowed soil — including furrowed subterranean soil — will gradually smooth itself out, at which point grass and other vegetation will begin to grow. Sand always appears as
~ and cannot become furrowed - as such, sand roads do not last as long as those made on ordinary soil.
Trees and Shrubs
Once you discover the caverns, subterranean trees and shrubs will begin to grow on any subterranean soil.