General situation: The main season crop is in the ground and mostly well-established in the northern end of the San Joaquin Valley. The next 10 days is forecast to range from the high 70's to mid 90's, which is ideal conditions for thrips to develop.
Resistance breaking strains of TSWV: Resistance breaking (RB) strains of the virus have now been confirmed pretty much across the whole range of tomato production so SW-5 varieties are no longer guaranteed to shrug off any early infections. After a few years of relatively simple TSWV management we're moving back into a period when a whole-system, IPM, approach will be needed to keep the virus at bay.
Thrips projections and management: We've extended the degree day model out to the end of July. Currently, the model is showing us that we're probably in the middle of the second post-winter population. Generation 3 adults will hit peak activity in the first week of June, with generation 4 adults following about three weeks later. These are the two key generations of thrips to control to prevent damage to the crop; growers who are considering investing in thrips control treatments are likely to see the biggest impact if treatments are applied any time from now through the end of June. We have had a few reports of scattered TSWV in crops and the aim now should be to stop thrips from spreading the virus from those few initial infections.