Improving Apple Scab Management in 2025: Lessons from 2024
Apple scab, caused by the fungus *Venturia inaequalis*, remains one of the most significant challenges for apple growers in Michigan and New York and across Northeastern North America. The 2024 growing season provided valuable insights into effective Integrated Pest Management (IPM) strategies to combat this persistent disease. By reflecting on lessons learned and leveraging tools and technologies, farmers can optimize their approach to apple scab management in 2025.
Lessons from the 2024 Apple Season
1. Weather-Driven Disease Pressure
The 2024 season was marked by fluctuating weather patterns that significantly impacted disease cycles. Prolonged wet periods during key infection windows, coupled with unexpected temperature shifts, created ideal conditions for apple scab outbreaks. Farmers who closely monitored weather data and adjusted their spray schedules accordingly saw better outcomes than those relying on fixed intervals.
Takeaway for 2025: Utilize weather monitoring systems and predictive models to time fungicide applications precisely. Tools like NEWA’s real-time weather tracking and agtech platforms such as Farmable can provide actionable insights into disease pressure.
2. Early Season Monitoring and Management
2024 reinforced the importance of early-season management to prevent primary infections and subsequent scouting to manage secondary infections. Farmers who monitored weather and disease forecasting tools during the green tip to petal-fall stages and applied protectant fungicides during this critical period had fewer secondary infections later in the season. Scouting after petal fall for primary infections helped growers to identify where primary infections had broken through and additional management was needed.
Takeaway for 2025: Begin monitoring disease forecasting systems as early as bud break and ensure that protectant fungicides are applied before or immediately following infection events. Early intervention remains the cornerstone of effective apple scab management.
3. Scouting for Primary Infections
Disease management is typically prophylactic, meaning trees are protected before infections take place. Once you notice symptoms, infections have already occurred.
Scouting for apple scab is still incredibly important. If primary infections are controlled early in the spring, no further management is necessary. But if primary infections take place, the lesions will produce more spores, leading to further infections that must be managed for the duration of the season. Scouting carefully after primary infection events can help identify infections early, to know if further management is needed, rather than getting a surprise later in the season.
4. The Role of Resistant Cultivars
Growers planting resistant or less susceptible apple varieties noted significantly reduced scab incidence. Although not a complete solution, integrating resistant cultivars into orchards provided a layer of protection, reducing the overall disease burden.
Takeaway for 2025: Consider incorporating resistant apple cultivars into planting plans. Diversifying with resistant varieties not only mitigates disease risk but also reduces reliance on fungicides over time.
5. Data Collection and Record-Keeping
Farmers who diligently recorded scouting data, spray schedules, and weather conditions gained a clearer understanding of what worked—and what didn’t—in their IPM programs. This helped them make more informed decisions throughout the season.
Takeaway for 2025: Emphasize detailed record-keeping as part of your IPM strategy. Use digital tools like Farmable to log field observations, track fungicide applications, and analyze trends across seasons.
6. Erratic weather makes management more challenging
Extreme and unusual weather patterns can have enormous, often unpredictable effects on agriculture, including disease forecasting. Unfortunately, we are seeing more frequent events like this, including drought, extreme rainfall, and early springs.
In 2024, a warm winter and early spring conditions resulted in early budbreak and phenology across the region (as much as two weeks early in much of Western NY). Ascospore maturity is typically correlated with temperature and tree phenology, so forecasting systems also predicted these spores matured earlier than average. The primary infection period, when ascospores are released, started earlier and perhaps lasted longer in 2024, meaning a longer window of management.
Longer wetting events and heavier than average rainfall throughout the spring also posed challenges. Infection events were longer with fewer windows in between for intervention. Fungicide residues are more easily washed off with more rainfall, making reapplication necessary, in one of the most busy parts of the season.
IPM Strategies for 2025: Building on What Works
Optimize Spray Programs
Incorporate a mix of protectant and systemic fungicides to combat both primary and secondary infections. Rotate fungicide classes to prevent resistance and rely on predictive models such as the NEWA Apple Scab Model: https://newa.cornell.edu/apple-scab to time applications well and reduce unnecessary applications.

Figure. Ascospore Maturity graph for Highland, NY in 2024 from the Cornell NEWA platform Apple Scab Model. Ascospore maturity can change based on actual green tip date, which should be entered by the user.

Figure. Infection events for Highland, NY in 2024 from the Cornell NEWA platform Apple Scab model. Infection events change based on actual green tip date, which should be entered by the user.
Make sure to use the models correctly. Input actual green tip date so that the model lines up with your site. Pay attention to infection periods, and make sure trees are protected during these events. Reapply to protect trees for the duration of the primary infection period, particularly if heavy rains wash off residues. Continue scouting after infection events to see if any primary infections occurred; if so, stay on top of fungicide program to prevent secondary infections for the rest of the season.
Strengthen Scouting Practices
Dedicate time for regular orchard inspections, focusing on early signs of infection. Train your team to identify symptoms accurately and consistently across all blocks.
Enhance Orchard Hygiene
Sanitation efforts, such as removing leaf litter and applying urea or dolomitic lime to accelerate leaf decomposition, proved effective in reducing overwintering inoculum. Make orchard hygiene a priority in late fall and early spring.
Leverage Technology
Agtech platforms can simplify IPM implementation by offering tools for digital scouting, spray tracking, and data analysis. Using platforms like Farmable to aggregate and analyze data can save time and improve decision-making accuracy. Farmable provides an intuitive platform designed to support apple growers in their IPM efforts. With tools for logging scouting observations, tracking spray applications, and monitoring weather-based alerts, Farmable enables smarter, data-driven decisions. By streamlining the organization of orchard data and connecting it with monitoring systems, the platform helps farmers stay ahead of apple scab challenges while maximizing efficiency and resource use.
Looking Ahead: Collaboration and Adaptation
The fight against apple scab is a dynamic challenge, requiring collaboration between farmers, extension agents, and researchers, and different in every year. Farmers are encouraged to participate in workshops and extension programs, like those offered by Cornell University, to stay informed about the latest IPM practices and technologies.
Additionally, as climate change continues to influence disease dynamics, flexibility will be key. Adapting to new patterns of disease pressure and taking a proactive approach to management will help farmers stay ahead of the curve.
By applying the lessons of 2024 and embracing an adaptive, technology-driven IPM approach, apple growers in Michigan and New York can improve their management of apple scab in 2025. Early scouting, precise fungicide timing, resistant cultivars, and robust data collection will be the foundation for a successful season.
For more Information have a look at our previous articles about IPM:
- Pest Monitoring & management
- Integrated Pest Management: Biological vs. Chemical
- Farmable and IPM: A Powerful Duo for Modern Agriculture
- What currently available technology best supports a farm in their implementation of IPM?
Feel free to reach out to us at support@farmable.tech with any questions or share your own experience with IPM. We’d love to hear from you!