Objective: to assess the severity of a forest fire and its impact on understory vegetation (shrubs, herbs, grasses) and on the chemical properties of the soil.Design/methodology/approach: in an area of 100 m2, individuals of shrubs, herbs and grasses were recorded. Soil was also collected in 6060 cm subsites in all sampling sites in three regions of a temperate forest considering the severity of the fire as intact, intermediate and severe.Results: it was found that the relative abundance of different life forms varied in relation to severity, only herbaceous benefited in intermediate severity, shrubs and grasses decreased. Soil pH and exchangeable cations Mg, Na, K and Ca increased as fire severity increased. N, P, K nutrients increased mainly in the intermediate severity, contrary to expectations for N.Limitations of the study/implications: not having more temperate forest zones replicated reduces the ecological patterns of understory vegetation succession and chemical soil changes.Findings/conclusions: the intermediate fire severity presented greater abundance of herbaceous plants. Similarly, the interchangeable cations, nitrogen, phosphorus and potassium increased in the same severity.
