The sudden emergence of black dots, occurring around three weeks before harvest on the apple variety Natyra® worries organic growers and researchers. This year at harvest spots were bigger and we also saw comparative symptoms on other varieties such as Topaz, Rewena and Wurthwinning. Due to the appearance of the bigger spots, there is a strong suspicion that it concerns the fungus E. pyri (also known by the name Topaz spot). Within this project, the first objective is to obtain short-term confirmation of the presence or absence of E. pyri as a pathogen. If it does not appear to be E. pyri, a microbiome analysis will be performed to determine the responsible pathogen. The second objective is to set up a sustainable control strategy (1) based on analysis of an obtained dataset with environmental conditions and (2) with the most efficient products, in terms of dosage, frequency and timing, so that at the end of this project the problems with this disease in organic farming are strongly reduced.