NAA welcomes Dr. Constance Hausman, one of the original authors of the first scientific paper on Beech leaf disease (BLD )in December 2018. BLD was discovered in 2012 on American beech trees in north‐east Ohio. Since then, it's spread beyond Ohio to Pennsylvania and Ontario, Canada, and has been found on American beech (Fagus grandifolia), European beech (F. sylvatica), and Oriental beech (F. orientalis). This pathogen has the potential to drastically alter the Eastern deciduous forests of the United States, and beyond. Learn how to recognize this disease, how it progresses, and the latest information about its possible cause.