Crop Disease Forecasting Tool Replaces Retired Apps
Published: 07/21/2025
The Crop Protection Network has launched the Crop Disease Forecasting Tool, a free, web-based resource designed to help users assess the risk of major foliar diseases in corn and soybeans. This tool replaces older apps like Tarspotter and Sporecaster, which are no longer supported. Built on years of university-led field research and modeling, the tool provides daily updates and a 7-day forecast using local weather data. It currently includes models for tar spot and gray leaf spot in corn, and white mold and frogeye leaf spot in soybeans- helping users make timely, field-specific fungicide decisions. Try the tool today: Crop Disease Forecasting Tool.
In addition to foliar disease forecasting, the tool now supports mycotoxin risk assessment.
Gibberella ear rot is caused by the fungus Gibberella zeae (synonym Fusarium graminearum). It is a consistently important mycotoxigenic fungus in the northern Corn Belt, producing deoxynivalenol (DON or vomitoxin), zearalenone, and other toxins. Corn is susceptible to Gibberella ear rot during silking. The DON model on the CPN Forecasting website is based on logistic equations developed by Paul and Nesi which calculate the probability of DON above 1 ppm at harvest. Risk scores are assigned based on probabilities formulated in the model using weather parameters around the corn silking growth stage. More Information About Gibberella ear rot and mycotoxins can be found below:
Screenshot of the Crop Disease Forecasting Tool running the Gibberella ear rot/DON model.
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