Soil Health Quantification Via SMAF and CASH in Different Agroecosystems in Ohio

Soil health refers to the ability of the soil to function as a living ecosystem to support plants, animals, and humans (Karlen et al., 1997; USDA-NRCS, 2019). Soil health is quantified by considering agricultural sustainability, environmental quality, and animal health. To understand soil health, researchers measure physical, chemical, and biological soil properties and interpret the results via soil health frameworks [Doran, 2002; Doran & Zeiss, 2000; Karlen et al., 2003 (see "Additional Resources")].

The Soil Management Assessment Framework (SMAF) ) and the Comprehensive Assessment of Soil Health (CASH) ) are two frameworks that offer comprehensive soil health quantification that can be easily interpreted by producers (Andrews et al., 2004; Moebius-Clune et al., 2016). SMAF and CASH follow a logical, three-step process:

1. Indicator selection.
2. Indicator interpretation into a unitless score.
3. Integration into individual and overall soil health scores (Figure 1).

Hu et al. (2025) examined the sensitivity of SMAF and CASH to detect soil health differences within different agroecosystems across forests, pastures, and organic and inorganic crop lands at Grace L. Drake Agricultural Laboratory, Wooster, Ohio. Outcomes from this work should help producers make better informed decisions on soil health protocols, soil health indicator selection, and on determining an on-farm soil health endpoint. Key findings of the Hu et al. (2025) study are described below.

Frameworks Sensitivity

Analysis of the overall soil health scores (Figure 2) revealed that the CASH framework had a greater capacity to differentiate among land uses and management practices when compared to SMAF. The superior responsiveness of CASH in this study is likely due to two factors:

1. Its scoring algorithms are particularly sensitive within cultivated sites.
2. The soil properties in Ohio more closely resemble those in the original dataset used to develop the CASH framework.

Soil Health Under Different Land Uses

Results indicated that the managed pastures (DP and BP) had the best overall soil health. The pasture sites consistently received the highest scores from both the SMAF and CASH frameworks because the conservation management practices (i.e., minimum soil disturbance, permanent soil cover) increase soil organic matter. Conversely, the poorest soil health conditions were observed in the evergreen forest (EF), which was characterized by extremely acidic soil, and in one of the conventionally tilled sites without drainage (UCD), which showed clear signs of deteriorated soil health conditions due to soil disturbance.

Benchmark to Calculate Soil Health Gap

Managed pastures showed greater overall soil health conditions and could serve as practical soil health benchmarks in the midwestern United States. Based on the results, undisturbed natural sites (i.e., forests) should not be used as benchmarks because their soil properties, which indicated extremely high organic matter or low pH, are often unachievable or unsuitable targets for crop production. Instead, a managed pasture is presented as an ambitious yet achievable goal. This is because pastures excel in the four key principles of soil health that translated into the best overall soil health scores in the study:

1. Minimizing disturbance.
2. Maximizing cover.
3. Maximizing living roots.
4. Maximizing biodiversity.

Additional Resources

• Soil Health
  (ohioline.osu.edu/factsheet/anr-0202)
• Physical Soil Health
  (ohioline.osu.edu/factsheet/anr-0203)
• Chemical Soil Health
  (ohioline.osu.edu/factsheet/anr-0204)
• Biological Soil Health
  (ohioline.osu.edu/factsheet/anr-0205)
• Soil Health Testing
  (ohioline.osu.edu/factsheet/anr-0206)

References

Andrews, S. S., Karlen, D. L., & Cambardella, C. A. (2004). The soil management assessment framework. Soil Science Society of America Journal, 68(6), 1945–1962.
doi.org/10.2136/sssaj2004.1945

Doran, J. W. (2002). Soil health and global sustainability: Translating science into practice. Agriculture, Ecosystems & Environment, 88(2), 119–127.
doi.org/10.1016/S0167-8809(01)00246-8

Doran, J. W., & Zeiss, M. R. (2000). Soil health and sustainability: Managing the biotic component of soil quality. Applied Soil Ecology, 15(1), 3–11.
doi.org/10.1016/S0929-1393(00)00067-6

Hu, X., Rakkar, M. K., Lyon, S. W., Armstrong, K. S., Jackson-Smith, D. B., Haden, V. R., Lorenz, N., Whitacre, S. D., & Ippolito, J. A. (2025). Soil health quantification via SMAF and CASH across diverse land uses. Geoderma, 461, 117492.
doi.org/10.1016/j.geoderma.2025.117492

Karlen, D. L., Ditzler, C. A., & Andrews, S. S. (2003). Soil quality: Why and how? Geoderma, 114(3–4), 145–156.
doi.org/10.1016/S0016-7061(03)00039-9

Karlen, D. L., Mausbach, M. J., Doran, J. W., Cline, R. G., Harris, R. F., & Schuman, G. E. (1997). Soil quality: A concept, definition, and framework for evaluation (a guest editorial). Soil Science Society of America Journal, 61(1), 4–10.
doi.org/10.2136/sssaj1997.03615995006100010001x

Moebius-Clune, B. N., Moebius-Clune, D. J., Gugino, B. K., Idowu, O. J., Schindelbeck, R. R., Ristow, A. J., van Es, H. M., Thies, J. E., & Shayler, H. A. (2016). Comprehensive assessment of soil health – The Cornell framework (edition 3.2). Cornell University.

USDA-NRCS. (2019). Soil Health.
fs.usda.gov/nac/topics/soil-health.php