Note: Not all indicated timings may be necessary for disease control.
| Disease | Fall | Delayed dormant | Green tip/ White bud |
Pink bud/ Full bloom |
Petal fall/ Cover sprays |
|---|---|---|---|---|---|
| Fire blight | 0 | 1 | 2 | 3 | 34 |
| Powdery mildew3 | 0 | 0 | 1 | 3 | 3 |
| Scab1 | 22 | 22 | 3 | 3 | 3 |
Rating: 3 = most effective, 2 = moderately effective, 1= least effective, and 0 = ineffective
| 1 | Protection of early tissue is important. Additional applications should be made according to infection periods as determined by the Mills table. |
| 2 | Disruption of pseudothecial (ascostroma) development (fall) and inactivation of overwintering twig lesions (delayed dormant); effects of these treatments on disease control is uncertain. |
| 3 | Early applications are most effective; additional applications are made if mildew continues. |
| 4 | Start management program at the beginning of bloom and continue through bloom including "rat-tail" bloom throughout spring. |
Several models are available for forecasting infection periods and treatment timing. Models include: Maryblyt, Cougar Blight, etc.
Acknowledgment: Adaskaveg et al., 2025. Fungicides, Bactericides, Biocontrols, and Natural Products for Deciduous Tree Fruit and Nut, Citrus, Strawberry, and Vine Crops in California.