Tar spot, a new disease of corn caused by the fungus Phyllachora maydis, was reported for the first time in Ohio at the end of the 2018 growing season. At that time, it was found mostly in counties close to the Indiana border, as the disease continued to spread from the middle of country where it was first confirmed in 2015.
Over the last few weeks, there have been several new, confirmed report of tar spot in Ohio, this time not only in the northwestern corner of the state, but also from a few fields in central and south-central Ohio. As was the case last year, disease onset was late again this year, with the first reports coming in well after R4. However, some of the regions affected last year had more fields affected this year, with much higher levels of disease severity.… Continue readingRead More »