Hot weather brings on more Armyworm

The armyworm has infested several fields more substantially and earlier than normal this year. Luis Espino used the degree day to predicted 5th instar armyworms would start showing up June 22. The heat from last week accelerated the armyworm growth in the field as reported in the UC Rice Blog.

We have been communicating with the Department of Pesticide Regulation (DPR) and they are relaying the information to the U.S. Environmental Protection Agency (U.S. EPA). The best update we can provide is the Intrepid section 18 specific emergency exemption is in the process as a top priority with expedited review. We no longer have the option for a crisis exemption, since the last two years resulted in an unprecedented approval through that process.

The DPR staff have been incredible team players in their responsiveness and ability to develop the justification for significant economic loss from the limited yield loss data we provided from last year. In the interim, please consider alternative insecticides as we do not have a firm timeline on the Intrepid section 18. The armyworm feeds on the levee watergrass before moving to the rice in the field. Some are controlling the watergrass on the levee as an attempt to keep the fields clear of armyworm.

Armyworm returns in 2017

Armyworm has returned to rice fields earlier than normal this year. The Intrepid section 18 emergency exemption has been submitted for approval. However, we currently do not have a date when it will be available – or if it will be offered. The yield damage data we received to support the significant economic loss was minimal. Without the necessary data, we crafted an argument we anticipate will adequately justify the section 18. In the interim, the alternative insecticides are an option when the worm reaches treatment threshold levels. READ MORE