Apples are an important specialty crop in New York State (NY), and NY is the second largest producer of apples nationwide, with more than half destined for fresh market. Of economic importance is managing apple scab, caused by Venturia inaequalis. Owing to fungicide resistance concerns, multi-site fungicides have become integral to apple scab management. Regulatory changes due to environmental concerns worldwide have caused severe restrictions or complete ban of usage of synthetic muti-site fungicides, hence there is a need to find an alternative management solution. The goal of this research was to manage apple scab by replacing synthetic multi-site fungicides with biopesticides and using modern planting systems and disease forecasting to time fungicide applications in light of regulatory concerns. The work completed in this thesis will help growers replace multi-site fungicides with biopesticides to manage apple scab using disease forecasting in light of climate change.