General Outlook It's 2022 thrips season. The first half of the winter was wet and cold, but since the turn of the year, we have seen next to no precipitation in the region. Temperatures have been more or less normal for the time of year and all in all it has probably been a reasonably good year for thrips survival as pupae in the soil over the winter. Unless we get some serious cold wet weather to round off the spring the prospect is that thrips numbers are likely to start building quickly over the next couple of months. The next 10 days or so will see changeable weather with a cool weekend and start to next week (with rain forecast for Saturday) giving way to a run of three or four days with temperatures in the high 80's. Those kinds of temperatures will accelerate thrips development.
Population projections Based on temperatures experienced at the monitoring site east of Stockton, the current projection is for generation 1 adults to peak around March 21, with generation 2 egg hatch peaking in mid April and generation 2 adults peaking in the first week of May. Unless you are in an area with a history of early TSWV infections and you suspect that the virus is already present in weeds or other crops close by, the chances are that the first couple of generations of thrips will be relatively free from virus and usually do not pose a serious threat to new tomato plantings.