Technical Abstract: Fusaric acid (5-butylpicolinic acid) was first discovered during the laboratory culture of Fusarium heterosporum, was one of the first fungal metabolites implicated in the pathogenesis of wilt symptoms of plants especially under adverse conditions. In addition to a primary role in plant pathogenesis, fusaric acid is mildly toxic to mice and has other pharmacological properties. During tests for control of the fungus F. verticillioides, it was determined that fusaric acid was produced in planta and appears to control the growth of a biocontrol bacterium. Since fusaric acid is considered a wilt toxin, we examined its in planta production and role in the wilt of field maize. Using plants infected with fusaric acid producing and non-producing strains of F. verticillioides, we isolated, identified, and measured fusaric acid in roots of seedlings grown with and without drought stress. It was determined that fusaric acid was produced in planta at the same concentrations regardless of drought stress, and there were no symptoms of wilt disease in the one field maize cultivar tested. Perhaps its major importance is as an antibiotic against bacteria that co-occur with Fusarium species on plants and in soil, suggesting that fusaric acid does not function solely as a wilt toxin in maize.