Fire Blight Disease Models

There are a number of computer disease models available which can forecast potential fire blight infection periods in apple and pear orchards. Some are relatively simple and can be operated by someone having average computer skills while others are more complex and require a higher degree of capability. While each model has its unique strengths, the predictive output should be reviewed carefully with the aid of a professional crop advisor (PCA) and/or extension specialists when a fire blight treatment program is considered. The information below is not exhaustive and is provided as a service for those interested in more information about fire blight disease prediction models. AgroSource is not responsible for the content or effectiveness of these resources.

Model: Cougarblight 2010 Ver. 5.0
Regional Limitations: None
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Description: A customized Microsoft Excel spreadsheet, Cougarblight is a risk assessment model for determining the potential for fire blight infection on flower blossoms. The model was developed by Tim Smith at Washington State University in the 1980s and has been a standard for fire blight risk assessment in the Pacific Northwest. Cougarblight estimates the level of risk for fire blight infection during the pre-bloom and bloom period based on temperature accumulation (degree days), forecast temperatures and moisture events, and the history of fire blight in or around an orchard the previous growing season.

Model: Decision Aid System (DAS)
Regional Limitations: Washington state only by subscription: $150/yr/site. Note: DAS allows importation of custom weather stations from other states and regions.
Description: The Decision Aid System (DAS), developed at Washington State University Tree Fruit Research and Extension Center, is a web-based integrated pest management decision support system based fundamentally on Cougarblight and provides interactive model feedback to users. DAS is updated by real-time state-wide weather data from NOASS, is user customizable by location and model and provides tabular as well as graphical illustrations of potential fire blight during bloom. DAS output is integrated with the WSU spray guide enabling recommended treatments to be reviewed from within DAS. DAS is also available for the iPhone.

Model: Enviro-Weather
Regional Limitations: Michigan state only.
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Description: Enviro-Weather, developed at Michigan State University, is an interactive weather-based pest, natural resources, and production management tool for Michigan growers. Enviro-weather is a web-based application offering a bloom-time fire blight interactive predictor module with links to real-time weather data, forecasts, and biological and other process-based models for assistance in operational decision-making and risk management associated with Michigan’s agriculture and natural resource industries.

Model: MARYBLYTE Ver. 7 for Windows
Regional Limitations: None
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Description: MARYBLYTE Ver. 7 for Windows is a stand-alone PC (Windows) application validated fire blight (all phases) forecasting software application. MARYBLYTE is offered free of charge but without support to growers, county agents, extension specialists, private consultants and researchers and is made available by West Virginia University, Tree Fruit Research and Education Center, Kearneysville, WV.