CRS degree day updates 2026
Biofix: March 1, 2026; First generation crawlers: 17 May; Second generation flight: June 14.
As of June 21, 2026, Tulare County has accumulated approximately 1924 degree days (base 53°F) since the March 1 biofix for California red scale. This indicates that third-generation male flight will start soon, as the population is close to ~2200 DD threshold for male flight. Expect crawler emergence in 2-3 weeks folllowing male flight (by July 15). Crawlers critical management window, as they represent the most susceptible stage for control. Orchards should be closely monitored for white caps and crawler activity using regular scouting and tape traps, with treatment decisions based on confirmed field presence rather than degree days alone. Third generation crawler emergence near 2750 DD (~3 weeks). All management decisions should follow UC IPM guidelines, with careful field-by-field monitoring due to variability in local conditions.
For more information on previous seasons DD and 30 year average.
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Individual field conditions may vary. Monitor Individual fields. For treatment recommendations UCIPM Guidelines for citrus