Tar spot of corn (caused by the fungus Phyllachora maydis) was first confirmed in the United States in 2015. In 2018, a yield-reducing epidemic of tar spot occurred in northern Indiana and in surrounding states. Following this epidemic, tar spot was detected in 172 counties across six states in the Midwest. Our knowledge of how to economically and sustainably manage this new disease is limited, but it is important to understand how to identify tar spot if it appears on your farm. This revised publication covers identification methods, potential impacts, and Indiana management options for tar spot.
Darcy Telenko; Gail Ruhl, Kiersten Wise, Tom Creswell