How to Manage Pests
Interactive Tools and Models: Spray Forecast for Tomato Powdery Mildew
Selecting a start date
The start date may not be before the first day of weather data available for a UC IPM weather station, or the first day of data in your weather file. Since the model bases its forecast on the latest 6 days of weather data, if possible select a start date at least 6 days before the current date.
Once a location is set up with its start date, you may not change the start date. However, you may create a new location with the desired date and delete the old location.
Note on estimated harvest date
Some recommendations are based on the proximity to harvest. Also, the program gives recommendations and allows you to enter sprays through the estimated harvest date only. You may change the estimated harvest date at any time, as needed to improve accuracy of the model recommendations as the harvest date draws near and to change the last date the model run.
A spray protects the crop for 10 days, with the day of the spray being counted as day 1.You may not enter spray dates that are before the start date or after the harvest date. If you enter a spray date that is after the end of the existing weather data, you will not see it reflected in recommendations until weather data has been added for that date.