By Luis Espino, UCCE Rice Farming Systems Advisor
By this time last year, we were seeing the peak of moth flight, with about 18 true armyworm moths per night, and almost no western yellostriped armyworm moths. This year, true armyworm moths are below 10 per night, except for a couple of locations in Glenn County. If we are going to experience an increase in flight, it might come in the next two weeks.
I visited fields of early headed rice in Butte and Glenn counties, and I could not find worms or found very few worms. I would say late planted rice may still be at risk, specially if we see the flight materialize.
Western yellowstriped armyworm remains a mystery to me. The numbers we have been trapping are variable, but we are seeing more than last year. However, I do not see them in the field.
I’d say we have two more weeks to worry about, and if numbers are still low, we may be out of the woods.
Graphs are here: http://rice.ucanr.edu/Armyworm_traps/