A survey of the fungal diversity associated with mixed pastures from Eastern Cape dairy farms in South Africa led to the isolation of 155 Fusarium strains that belong to the Fusarium incarnatum-equiseti species complex (FIESC). Using single and multigene phylogenies based on partial sequences of the translation elongation factor 1-alpha (TEF), calmodulin (CaM), and the partial RNA polymerase second largest subunit (RPB2) genes, we identified 11 species. They included F. brevicaudatum, F. clavus, F. coffeatum, F. croceum, F. goeppertmayerae, and F. heslopiae, with five species that were found to be new. Based on morphological and phylogenetic data, three new species are formally described here as F. cumulatum, F. mariecurieae, and F. pascuum. We also provided a description for F. goeppertmayerae, as the authors who identified and named this species did not include one. We have chosen to not describe the remaining species, as our cultures lack proper morphological structure development. This study shows that mixed pastures harbour a diverse range of Fusarium species and highlights the need for further studies into their potential to impact animal health.