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WSU Decision Aid System Update April 2024

Written by Liesl Oeller, Washington State University, April 1, 2024

The field season is well under way and the DAS team is excited to roll into April. Now is the perfect time to subscribe to DAS!

We are having a considerably warmer spring than last year. As of April 1, 2024, we have significantly surpassed degree days accumulated at this time in 2023, when we had a record cold spring.

screen shot of DD accumulated on April 1st by year
Timeline comparing number of degree days accumulated on April 1st in the last five years. Far more degree days have accumulated in 2024 than 2023.

As we move into April, models are becoming active and tree fruit pests are emerging. The pear psylla model is one to look at. Populations in central and southern Washington are increasing, with nearly all overwintering adults emerged and first-generation eggs beginning to hatch.

Codling moth (CM) activity is also expected to begin in central and southern Washington. CM emergence is predicted at 175 degree days, which places like Pasco and Vantage will reach next week.

screen shot of phenology map for codling moth
Map of Washington state showing CM degree day accumulation across the state. Central and southern Washington will reach 170 degree days by next week, when CM emergence is predicted.

You can use our time machine tool to look back on weather data from the last five years and see how 2024 compares. You can also set up alerts for when key pests are emerging for timely management.

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!

Contact

Liesl Oeller
Liesl Oeller
Washington State University
elisabeth.oeller@wsu.edu
(509) 335-5815

 


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