What type of soil typically has the highest runoff potential?

Clay soil typically has the highest runoff potential due to its fine particle size and compact nature. When rainfall occurs, clay soil's dense structure limits the infiltration of water into the ground. The small pore spaces retain water on the surface, leading to increased surface runoff. This runoff happens because the water cannot easily permeate the soil, resulting in a higher likelihood of pooling and flowing away rather than being absorbed.

In contrast, sandy soil is characterized by larger particles and greater permeability, allowing water to penetrate quickly and reducing surface runoff. Loamy soil, which is a mixture of sand, silt, and clay, tends to balance water retention and drainage, resulting in moderate runoff potential. Peaty soil has high organic content and can absorb considerable water, which lowers its runoff potential. Therefore, the properties of clay soil make it particularly prone to higher runoff compared to the other soil types listed.