Other propertues of soil include:
plant roots and burrowing animals aerate the soil by creating space between sticky clay particles.
- Color: These organisms also add organic matter to the topsoil;
prairie soils thus have a rich topsoil that gives it a dark color
- "black earth".
The calcium-rich limestone bedrock in northern Illinois gives the soil a
pH greater than 7; native plants are adapted to this basic/alkaline soil.