California

Issue #35, Fall 2016

Single Red Rice plant, RReseiarcch Boae rd mid-season for fields infested with weedy rice. It Weedy Rice is up to the rice in - dustry to make Folks, we have a problem. We can sure infested fields deny it, ignore it, or hope it will go away are managed to re - – but we still have a problem. We hope duce infestation you will engage with us and work to levels and eventu - eradicate weedy rice (a.k.a. red rice) in ally get rid of this California. weed. Could it be a big problem here? Let’s Do we know all the answers yet – No. look at the South. Timothy Blank, CA The researchers and farm advisors have Crop Improvement Association, states put together Best Management Practices that high infestations in the South have re - with our current knowledge. Here is sulted in yield reductions of over 60%. A what you can do today: 2008 survey in Arkansas found that 62% of rice fields are infested to some degree. Before Harvest California has been fortunate. Over Weedy rice plants are easiest to iden - the last 100 years of rice production tify at the heading stage, here, there have been periodic infesta - UCANR brochure, tions. Most of these infestations were http://rice.ucanr.edu/files/239170.pdf. Weedy eradicated or have been taken out of rice The three consistent characteristics are rice can production. So things have gone well – 1) red colored bran, 2) shattering, and 3) be up to 2003 when weedy rice was found seed dormancy. It can be distinguished awned in rice fields in Colusa and Glenn coun - from most conventional rice varieties in or ties. Efforts were made to eradicate that it has lighter green leaves, rougher awnless weedy rice in these fields, but the popu - leaves, a wider canopy, and is taller. If lations have persisted. In addition, sev - you have suspect plants: 1) take a trash eral new populations have been bag and capture the seeds so you don’t discovered in almost all rice producing spread the problem, 2) dig up the plant, In This Issue counties. Luis Espino, UCCE rice advi - and 3) bring it to one of the county farm Weedy Rice ...... 1 sor, states that the known infestation is advisors for identification. about 8,000 acres. The industry needs to Whitney Brim-DeForest .....2 be very diligent and proactive if we are going to beat this infestation back. There are no regulatory implications

California Rice Research Board Page 1 During Harvest Isolation is the key. If you have a field where you might have weedy rice, har - vest it, but DO NOT con - taminate other fields by moving equipment that may carry till before flooding in spring, 2) Close Whitney Brim-DeForest weedy rice seeds from one field to the drains, flood, and allow water to sub - Meet the newest UCCE rice advisor, next. Best option – harvest the contam - side, 3) Wait for weedy rice to emerge Whitney Brim-DeForest. She will be inated field last. Next best option – clean (around 2 weeks) and spray with based out of the Sutter-Yuba office, but all harvesting equipment thoroughly be - glyphosate, 4) when soil is dry enough will serve Placer and Sacramento coun - fore moving from the affected field to (about two weeks), disc soil, 5) Close ties as well. She holds a Ph.D. in Horti - the next field. drains, flood, and allow water to sub - culture and Agronomy and an M.S. in Make sure paddy rice from an af - side, 6) repeat glyphosate application International Agricultural Development fected field does not get into the seed about two weeks after weedy rice (both from UC Davis), and a double channel, even for your own fields. seedling emergence. B.A. in Biology and Music from Brown Straw should be cut as low as possible If planting the field, use certified University. Before starting her graduate to the ground to facilitate burning. If you seed . Certified seed has zero tolerance work, she served as a Peace Corps Vol - are going to bale the straw, don’t cut it for weedy rice. Saving seed can con - unteer in Senegal, West Africa, for three especially low so there will be some - tribute to the spread of weedy rice, and years, where she worked with growers thing to burn. is not recommended at this time, both in a variety of crops, including rice, After Harvest for those growers that have a confirmed sorghum, corn, and cowpeas. Since infestation and for those that do not. 2012, she has worked at the Rice Ex - Harvesting equipment (combine, Consider using the stale seedbed tech - periment Station in Biggs, CA, manag - bank outs, trailers, etc.) should be thor - nique if you can. Contact your farm ad - ing the field trials for the UC Weed oughly cleaned in the affected field to visor for more information on how to Science program in rice. make sure there is no carry over of properly implement the stale seedbed weedy rice seed to other fields. Clean - technique. The graphic shows the basics. ing should include the removal of plant Also, details may be found on the RRB material from the equipment including website (carrb.com) under the Newslet - mud from tires or tracks that may con - ter section, Summer of 2009, Got Water - tain seeds. grass. Details can be found under Annual If possible, burn the affected field this Reports, 2011 and 2012, Full report link, fall. Make contaminated fields your top Weed Control in Rice, Objective 3. burning priority. Prioritization of fields The Future will occur at the county level, so notify your County Ag Commissioner if your The Weedy Red Rice Task Force has field is infested. Please follow the rules been reestablished to determine the most regarding burning. Take measures to effective path to eradicate weedy rice. have the most effective burn (raking, Greenhouse studies will be conducted spreading, favorable conditions). Con - over the winter and projects are planned sider coming back after burning the field for the spring to examine the best man - with a propane burner to burn exposed agement methods. Expect further infor - seeds on the soil surface. This practice mation in 2017. is most effective and reasonably safe No organization can do this alone. It Rice Farm Advisor only after open field burning. takes your individual effort to monitor Contact Numbers DO NOT perform fall tillage. This your fields. It takes your individual de - cisions to get rid of this pest. We en - Whitney Brim-DeForest: will bury weedy rice seeds and stretch 530-822-7515 the infestation out for years to come. courage you to join with the industry to Luis Espino: 530-458-0570 Next Season make California a weedy rice free state Cass Mutters: 530-538-7200 Fallow the field if you can. Recom - mended fallow management: 1) do not . Page 2 California Rice Research Board