Thrips/TSWV status in Yolo & Colusa

With a dryer-than-average winter, warm nighttime temperatures, and record-breaking high daytime temperatures in March, 2026 is off to a warm start.   Figure 1. Recorded temperatures (blue bars) between 10/01/2025 and 10/23/2026 for Davis, CA, compared to our normal temperature range (beige…

General outlook & thrips population Tomato planting is over, and with the excellent weather we have been having fields are progressing well.  Adult 3rd generation thrips are peaking, and over the next few weeks will be laying their eggs. Any thrips that acquired the virus as larvae by…

General outlook & thrips population Thrips population predictions are similar to last week’s update. Generation three is maturing, and adults are predicted to peak 6/8. For most crops the 3rd and 4th generations will present the highest risk of TSWV spreading and causing yield loss.  …

General outlook & thrips populationAs planting wraps up, temperatures remain similar to long-term averages. Thrips population predictions are similar to last week’s update. Generation 2 adults peaked a couple weeks ago; generation three adults are predicted to peak 6/8.  The 3rd and 4th…

General outlook & thrips populationPlanting will be wrapping up over the next couple of weeks, though the heat wave coming up next week may cause delays. In general, it’s been good spring weather and earlier plantings are progressing well. The warm weather in the forecast has pushed up population…