The soil can be broken down into several different horizons (layers). Each horizon is made up of different materials. The top most layer is organic matter. This is mostly made up of dead and decaying matter such as leaves and other organisms. Topsoil is the layer right below organic matter. It is very fertile and where plants get most of their nutrients in order to grow. Subsoil is mostly made up of sand and clay within Iowa's geology. Plants will send down their roots here mostly to find water or harder to find minerals. Parent material is mostly undeveloped bedrock, or other material, where soil comes from. Bedrock is the lowest layer in which is the hardest layer. For more information about Iowa soil click on this link.

The main use for these hatchings is to describe the ground condition below in a section drawing. Inspired by geological and architectural hatching conventions, these hatchings are meant to describe the ground condition in more detail than the a black or white poche. Each hatching marks the different soil layers that are important for agricultural purposes, but can be applied to other contexts as well.

Click on the image to access Adobe Illustrator swatch textures depicting soil horizons.