Updating the Armyworm Fight

Updating the Armyworm Fight

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:

More Armyworm Stories

Highest Armyworm Numbers Expected Soon and Inspection Tips

Highest Armyworm Numbers Expected Soon and Inspection Tips

The University of California Cooperative Extension (UCCE) says the next several days will be critical for growers to monitor their fields, and potentially make any necessary treatment decisions, as armyworm numbers will be at their highest very soon.

As expected, moth numbers peaked last week. Utilizing annual trend data and on-site monitoring, the UCCE says worms in the field will peak this week and next.