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.