Two rounds of sampling were conducted since the last update. GWSS activity has declined sharply as is typically the case this time of year. However counts remain higher than usual in most years

In the most recent sampling, collected last week, a total of approximately 140 GWSS adults were caught on the 112 traps deployed. 31 traps recorded a GWSS, five of which captured 10 or more. Traps with GWSS were primarily found in three main clusters in different parts of the valley

Relatively high GWSS counts at this time of year are not necessarily cause for concern. That's because any vines they might be infecting this late in the year are likely to recover over the winter without any lasting effects of Pierce's disease. [Infections early in the season, especially Spring and early Summer, are a much bigger concern. At some point we'll revisit what's known about this overwinter recovery phenomenon, which is a fairly unique feature of the PD pathosystem.] Nonetheless, it is worth tracking whether GWSS activity remains high through the Fall and Winter as it can be a harbinger of problems that may arise in the Spring and Summer. More on that later 

Please contact Matt (mattd@ucr.edu; 951-255-2807) for more information