- Author: Bruce A Linquist
- Editor: Taiyu Guan
Based on early projections, 478,000 acres of rice were planted this year. This is down 37,000 acres from last year. Lower acreage is in part due to a large rainfall event on May 4 and 5 which prevented some planting. This rainfall also delayed planting by about three days (50% planted on May 15 compared to the average of May 12 - according to the USDA). That said, the 50% harvest date was October 8 which is about average. Thus, the season length was a bit shorter (146 d from planting to harvest) which may be due to a warm summer and favorable harvest conditions with little to no rain.
Speaking of weather, July was an exceptionally hot month. For most rice, July coincided with panicle initiation through the booting stage. I regularly analyze weather data from CIMIS stations in the rice growing area of the Sacramento Valley. CIMIS has weather data going back to 1984. On average, July maximum temperature is 92.3 oF. This year, it was 97.6 oF and was the hottest on record since these records first started being tabulated. This also coincided with the warmest average nighttime temperatures (62.2 oF), which was 2 oF above average. The September average maximum temperature (91.2 oF) was also the hottest it has been since 1991 when it was 92.5 oF. However, September average nighttime temperatures were average.
Based on data from Dustin Harrel at the Rice Experiment Station, roughly 94% of the acreage was planted to medium grain varieties this year. The remainder was planted to short (4%) and long (2%) grain varieties. Of the medium grain varieties, M-206 was the most widely planted (27%). The other main medium grains (M-105, M-209, M-210, and M-211) represented between 14 and 19% of the medium grain acreage.
Talking with others in extension, this year we also saw a lot of fields where watergrass got out of control, in addition to a lot of redstem. Two relatively new herbicides were used this year: Zembu (pyraclonil) and Cliffhanger (benzobicyclon). While results were generally, in some cases there were issues that need to be worked out to ensure effective control. Pests and diseases were not a huge problem and were generally within typical ranges.
Based on personal communications with growers, farm advisors and mills, yields are a bit lower than average. Lower yields are likely due to a later planting date and warmer than normal growing season temperatures. High nighttime temperatures can reduce yields due to increased nighttime respiration. We have also heard reports of lower than normal head rice yields. Low head rice is being reported for all varieties but especially M-211. One reason for this is, as mentioned above, September temperatures (during grain fill) were warmer than normal.
- Author: Timothy Blank
- Editor: Taiyu Guan
Rice acres approved for seed production in 2024 totaled 24,000 acres, of which, 872 acres were in the Quality Assurance (QA) program. The seed production acreage in 2024 was a 3818 acre decrease from 2023, but it is worth noting that rice seed producers generally overproduce seed and there should be ample seed in 2025.
In 2024, there was production of 38 rice varieties (9 long grain, 17 medium grain, 12 short grain). Seed production exceeded 1000 acres only for the 5 Calrose varieties. Of the Calrose-type varieties, the current ranking in acres approved is M-206 (5583 acres), M-211 (3980 acres), M-105 (3640 acres), M-209 (3431 acres), and M-210 (3003 acres). These 5 varieties made up 81% of the seed production. Some trends to note:
- M-206 saw a ~2K acre decrease in acres approved compared to 2023, and there are no new fields being transitioned into M-206 (for additional 2025 seed production).
- M-211 had a 606 acre decline in seed production, but also had 494 acres in transition to seed production for 2025.
- M-209 acres had a 206 acre decline in seed production, with 78 acres in transition to seed production for 2025.
- M-210 and M-105 had increases in seed production by 152 and 330 acres, respectively. M-210 and
- M-105 also had increases of 774 and 1011 acres, respectively, in transition to seed production for 2025.
To summarize, M-206 is trending downward, and M-210 and M-105 are trending upward.
More acreage details and analysis can be found on the CCRRF website: https://crrf.org/
Seed Field Inspections:
~100 acres of seed were rejected due to the presence of weedy red rice. There were additional partial rejections due to excessive weeds and other varieties. Several Certified class fields required roguing due to excessive off-types. Incidence of rice blast was rare this year.
The Certified seed and QA programs ensure that every rice seed field is inspected by field inspectors from the California Crop Improvement Association, and every seed lot is tested, to ensure that planting seed meets industry expectations for quality seed.
- Editor: Taiyu Guan
The following description has been endorsed by the Weed Science Society of America, Entomological Society of America, and American Phytopathological Society.
1: What is the Endangered Species Act (ESA)?
The Endangered Species Act is a long-standing federal law, first passed in 1973, which requires government agencies to ensure any actions they take do not jeopardize a species that has been federally listed as endangered or threatened. When an agency has a proposed action that might affect a listed species or its habitat, they consult with one or both of the agencies that helps enforce the ESA, the U.S. Fish and Wildlife Services or the National Marine Fisheries Service (this is known as “a consultation” with “the Services''). The Services then may recommend changes to the project or action to protect listed species or habitats.
2: How does the ESA affect pesticide use?
The Environmental Protection Agency (EPA) Office of Pesticide Programs (OPP) is the federal agency that regulates pesticide use. Because the use of pesticides can affect animals and plants (or their habitat), pesticide registrations are considered “actions” that would trigger an endangered species consultation.
3: Why am I hearing about the ESA and pesticide use now?
Due to the complex nature of the process, the EPA has not fully completed the required endangered species consultations with the Services for pesticide registrations in the past, which has left many of those pesticides vulnerable to lawsuits. Courts have annulled pesticide registrations which has led to their removal from market. To make pesticide registrations more secure from litigation, ultimately all pesticide registrations will comply with the Endangered Species Act (https://www.epa.gov/endangered-species).
4: How will this affect the pesticide I use today?
Many pesticide labels will likely have changes that could include:
- Requirement to check the EPA's Bulletins Live! Two website and follow current ESA restrictions for the pesticide product in the bulletin (https://www.epa.gov/endangered-species/bulletins-live-two-view-bulletins)
- Measures to reduce spray drift
- Measures to reduce runoff/erosion
- Other measures to reduce pesticide exposure to listed species and their habitat
In short, farmers and applicators should expect to see some new application requirements on their pesticide labels. But there is no need to panic. To date, no pesticide has ever been fully removed from the market based solely on endangered species risks, and that remains an unlikely scenario in the future.
5: Why does complying with the ESA matter?
By starting to fully comply with the ESA, EPA anticipates that this will give farmers and applicators more stable, reliable access to the pesticides they need. Furthermore, the ESA has been successful at bringing back some species Americans care about – such as the bald eagle or the Eggert sunflower – and restoring them to healthy populations, which has benefited the natural and cultivated ecosystems that agriculture (and society) rely on.
- Author: Luis A Espino
It is time again for the Rice Diseases Survey. The objective of the Survey is to document the incidence of rice diseases in Sacramento Valley rice fields so that the Air Resources Board agrees to continue to allow the rice industry to burn up to 25% of the acreage. Every five years, the Board has to re-approve the straw burning program. One of the reasons for letting growers still burn is disease control. Therefore, it is important to show that diseases are still present in rice fields. This is the third Rice Diseases Survey Cooperative Extension is conducting. The first was in 2014 and the second in 2019.
A crew of four to five will be stopping in random fields in the major rice producing counties and inspecting for the presence of diseases in 30 sites in each field. We will look for stem rot, aggregate sheath spot, kernel smut, and blast. The precise location of each inspected field won't be disclosed, only the general location and County.
If you have any questions or concerns, contact me at laespino@ucanr.edu or 530-635-6234.
