What should be determined when evaluating mollic soil?

When evaluating mollic soil, the determination of cumulative thickness with base saturation (BS) at or above 50% is essential. Mollic soils are characterized by a dark, organic-rich surface horizon that is at least 25 cm thick. One of the defining features of mollic soil is that it typically has a high level of base saturation, which indicates a significant presence of essential nutrients that are vital for plant growth. This high base saturation often reflects better soil fertility and improved nutrient availability.

In practice, when assessing mollic soils, ensuring that the cumulative thickness of the horizon meets the criteria with base saturation levels at or above 50% helps confirm the soil's classification. This is crucial for soil taxonomy and for understanding the soil's potential applications, particularly in agriculture.

The aspects related to minimum thickness, presence of rock fragments, and phosphorus content, while potentially relevant in other contexts, do not directly pertain to the primary characteristics used for identifying and classifying mollic soils. Therefore, the focus on cumulative thickness in relation to base saturation is key in this evaluation.