Type of soil that forms in grasslands

Mollisols

Explanation:

The soil of the temperate grasslands is deep and dark, with fertile upper layers. It is nutrient-rich from the growth and decay of deep, many-branched grass roots. The rotted roots hold the soil together and provide a food source for living plants.

Mollisols

Explanation:

Because these temperate grasslands have cold winters, and warm summers, and have medium to low precipitation. They form in areas that are too dry to be forested, but too wet to be desert. Most of the prairie soils are called Mollisols (latin for soft), because of their deep, dark layer of topsoil.