- Author: Neil McRoberts
General outlook After the extended cool spring, it looks like we have settled into typical summer weather for the Central Valley. Temperature projections for the next 7-10 days are in the high 80's to mid 90's F - perfect conditions for thrips development. Late-planted crops could have a long way to go before flowering and fruit set, which is when the threat of serious yield loss from TSWV decreases. The take-home is that with thrips activity certain to increase and crops relatively late, the risk of damage from TSWV could be high if the virus shows up in the near future.
Thrips generation timing We have extended the projections out to the end of July. Generation 3 adults are projected to peak in the next 5-6 days. Generation 4 will peak in the last week of June, with Generation 5, peaking around the third week of July. If you are planning to apply treatments to control thrips/TSWV, the next 4-6 weeks will be the period that will provide the best result for the investment. Since reported TSWV levels across the area are low, suppression of Generation 4 with treatments applied soon will delay the development of TSWV and allow crops a chance to grow past the most vulnerable period.