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WSU Decision Aid System Update June 2023

Written by Liesl Oeller, Washington State University, June 1, 2023

The season is well under way, and fruit has begun to develop. Below are updates on the apple bloom and apple sunburn models. For updates specific to your location, subscribe to DAS.

Apple Bloom Model

Summer is here and the apple bloom model has completed in most areas of Washington. If you’re not familiar and have interest in using it next year, our model shows current and forecasted stages for apple bloom for Ambrosia, Cripps Pink, Gala, and Red Delicious.

Figure 1. The chart shows the current and forecasted apple bloom stages for May 2023.


Apple Sunburn Model

As apples continue to develop and the summer heat progresses, the DAS apple sunburn model becomes important to check. This model allows you to enter your apple cultivar, fruit diameter, and canopy density. It then uses temperature, cloud cover, humidity, and wind speed data to predict apple sunburn risk. As always, management options for the day’s conditions and predicted risk are included. We hope you find this tool useful!

Figure 2. Chart showing the sunburn risk of apples in Wenatchee on May 31, 2023. The chart includes the day’s conditions including temperature, cloud cover, humidity, and wind speed as well as management options.


New DAS Features

Check out our new tools to make your life easier this season! Our time machine tool allows users to go back up to 5 years in history to view output of any DAS model. Checking degree day accumulations for past years may help you better plan the timing of upcoming management. Our other new alerts feature provides advance alerts of when key events, like degree day accumulation and life stage emergence, will occur. Sign up for these email or text alerts today!

For weekly updates on DAS models and tools, subscribe to our mailing list. Now is the perfect time to subscribe to weather stations on DAS, get started today!


Liesl Oeller

Liesl Oeller
Washington State University
(509) 335-5815


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