Which type of soil would require the highest lime application to achieve the same target pH?

To determine which type of soil would require the highest lime application to reach a target pH, it's important to consider both the existing pH and the characteristics of the soil, specifically the clay and organic matter content.

Soils with a lower pH value typically require more lime to reach a neutral pH. In this case, the soil with a pH of 5.0 is more acidic than other options, making it a prime candidate for significant lime application. The presence of clay also influences the lime requirement; higher clay content tends to hold more cation exchange capacity, which can require more lime to alter the pH effectively.

In this scenario, the soil with a pH of 5.0, 30% clay, and 1% organic matter would generally demand the most significant lime application. The high clay content suggests that the soil has a substantial ability to retain nutrients and may require more lime to change the pH due to its chemical properties. Additionally, the low organic matter content means there are fewer natural buffers present, requiring an increased lime application to achieve the desired pH adjustment.

While other options may have varying combinations of pH and organic matter, none align with the combination of low pH and high clay content