Bulletin #1016, Loose Smut of Barley and Oats (PDF) By Steven B. Johnson, Extension crops specialist, University of Maine For information about UMaine Extension programs and resources, visit extension.umaine.edu.Find more of our publications and books at extension.umaine.edu/publications/. Smutted head in the field. Photo by Steven B. Johnson. Loose smut of barley is caused by the