Researchers identified a new fungal disease affecting East Asian hogweed, an edible herb used in traditional medicine. The disease, called leaf spot, was caused by a previously unknown subspecies of fungus named Didymella acutilobae subsp. heraclei. Using genetic analysis and laboratory testing, scientists confirmed this fungus is responsible for infecting hogweed plants in Korean fields. Understanding this pathogen is important for protecting this valuable medicinal plant.