Thrips/TSWV status in Yolo & Colusa

General situation Almost all tomatoes are now in the ground. New TSWV infections will cause more yield loss in later than earlier plantings since the younger the plant is when it is infected, the more severe the disease will be.

General situation Temperatures over the past few weeks have been in the 80s and 90s, ideal conditions for thrips development. The hot weather coming up is also expected to accelerate thrips development and activity.

General situation Above-average temperatures this week compensate for below-average temperatures last week, and thrips population projections remain similar to earlier predictions. Thrips population Generation 2 adult thrips are peaking now, and will be laying their eggs.

General situation Unseasonably cool weather has slowed thrips population projections slightly. However, temperatures may be into the 90s by the end of the week and we expect to see populations continue to develop. Thrips population Generation 2 adult thrips are peaking in the coming week.

General situation Temperatures remain close to historic normals, and are predicted to remain moderate for the next few weeks. Planting is progressing throughout the Sacramento Valley. I've started to see some early TSWV infections in March-planted fields in Yolo County.