- Author: Whitney B Brim-Deforest
- Posted by: Gale Perez
This year brings several new chemical tools to California rice. With many herbicide-resistant species as well as emerging problematic weed species, the new chemistries are a welcome tool for managing resistance and preventing the selection of resistant biotypes.
Last year, we had use of Loyant® CA Rinskor™ active (florpyrauxifen-benzyl) for the full season (registered late in 2022). Loyant®, which is an auxin mimic, is applied as a foliar product. It gives additional options for early-season control of sedges and broadleaf weeds, and although not strong on watergrasses when applied alone, provides added control when tank-mixed with other herbicides for grass control. Based on data collected in 2022-2023, two good...
- Author: Whitney B Brim-Deforest
- Author: Roberta Firoved
- Posted by: Gale Perez
California rice growers will have a new herbicide available this year: Cliffhanger™, manufactured by Gowan Company. The active ingredient is benzobicyclon, which is the same as one of the two active ingredients in the currently registered herbicide, Butte®. Cliffhanger™ is a soluble liquid formulation (SC) which can be applied by ground-rig or airplane, including as a direct-stream application into the water. In contrast, Butte® is a granular formulation, as a pre-formulated mixture of benzobicyclon and halosulfuron. To use either product, applicators must attend a training and be certified.
Dates for the training are posted on the California Rice Commission calendar
- Author: Whitney B Brim-Deforest
- Posted by: Gale Perez
Background
White water fire (Bergia capensis) was found in September of 2023, by the Butte County Agricultural Commissioner's office in a rice field in Butte County. The weed was identified by the California Department of Food and Agriculture (CDFA.) It is the first find of this weed in California, and possibly in the United States. It is native to Africa, southern China, and tropical Asia, and it is known to be in rice fields in Europe, Central and South America, as well as the Caribbean. It was likely transported in seed to rice-growing areas and has been established in those locations for many years.
In Butte County, the weed was only found in one rice field, and the Agricultural...
- Author: Sarah Lorraine Marsh
- Posted by: Gale Perez
My name is Sarah Marsh, and I am excited to join UC Cooperative Extension as the new Rice Farming Systems Advisor serving Colusa and Yolo counties. I will be based out of Colusa at the Colusa UCCE office. I grew up on a diversified row-crop and orchard farm in Arbuckle and am grateful for the opportunity to serve the community in which I was raised. After completing my undergraduate degree in Plant and Environmental Soil Science at Texas A&M University, I obtained a M.S. in Horticulture and Agronomy at UC Davis, where I worked with Dr. Kassim Al-Khatib in studying weeds and herbicide resistance in rice agroecosystems. I have since worked in rice...
- Author: Aaron Becerra-Alvarez
- Author: Sarah Lorraine Marsh
- Author: Kassim Al-Khatib
- Posted by: Gale Perez
A new herbicide for early-season weed control in water-seeded rice will be available soon. The herbicide active ingredient (a.i.) is pyraclonil, which will be trademarked as Zembu™ (1.8% a.i.) by Nichino, America Inc. The mode of action is a protox porphyrinogen (PPO)-inhibitor or Group 14. This herbicide is formulated as a granule and will be used as a residual preemergence for application on the day of seeding onto flooded fields. The use rate is 14.9 lbs ac-1 applied by air. While this herbicide is not a new mode of action for water-seeded rice, it is a new mode of action for early-season residual weed control. Pyraclonil is widely used for weed control in paddy fields worldwide and is the most commonly utilized...