Which factor is NOT typically evaluated in a forest health assessment?

The assessment of forest health includes several critical factors that contribute to the overall well-being of the forest ecosystem. Tree vitality is evaluated to understand the health and growth of individual trees, as it influences the forest's capacity to sequester carbon and provide habitat. Species diversity is also a key component, as a diverse array of species can enhance resilience against pests, diseases, and changing environmental conditions. The presence of pests and diseases is monitored to identify threats to tree health and forest integrity.

Soil erosion rates, while a relevant environmental consideration, are not typically a direct focus in forest health assessments. Instead, forest health assessments are more concerned with biological indicators and the condition of plants and organisms within the forest. Soil erosion may be assessed in the context of land management or conservation practices but does not directly reflect the health of the forest in terms of its flora and fauna. Thus, among the options provided, evaluating soil erosion rates is less aligned with the core elements that define forest health.