The following update is from University of California Cooperative Extension Rice Farm Advisor, Luis Espino:
Week of June 29
On average for the Valley moth captures are going down. In a few fields moth captures are still increasing. The peak of larval activity occurs a week after the peak of moth catches, therefore right now we are seeing worms in the field. In two fields I checked, I found 10 large worms per 10-minute search. In these fields, defoliation was limited to lower leaves and does not warrant a treatment. Other fields had much lower number of worms.
I have asked a few PCAs about worm activity, and all report that worm numbers are low and defoliation small. However, worm activity will continue for another week, so keep monitoring.
For more information, click on the link below for the Armyworm Monitoring Website.
Photo credit: Luis Espino