As many of you are aware, many of our grass species in California rice are resistant to multiple herbicides. Late watergrass aka "mimic" (Echinochloa phyllopogon), early watergrass (E. oryzoides) and barnyardgrass (E. crus-galli) are among some of our most competitive weed species, causing large yield reductions when uncontrolled.
One of the last remaining chemicals that our grass species are not yet resistant to is pendimethalin. Commercial formulations for pendimethalin registered for California rice are Prowl H2O and Harbinger. Prowl H2O is a delayed pre-emergent herbicide applied onto dry, drill-seeded fields. Harbinger is also a delayed pre-emergent herbicide, but the Harbinger system can be used in fields that are seeded by air. Both are viable uses of the chemical, and which one you choose will depend on your available equipment. For more information on how to apply, refer to the product labels.
Although I have used Prowl H2O in field trials and have a pretty good idea of its efficacy, I was curious to see how Harbinger looked in the field, since I have not yet had the opportunity to use it in a trial. I recently visited Rice Researchers, Inc., a rice breeding facility in Glenn County, where they are using a Harbinger-based program, for the second season. The photo (below) shows the rice at about 30 days after seeding. No weed species were present in the field. This is after one delayed pre-emergent Harbinger application.
It is too late to utilize pendimethalin this season, but for help incorporating pendimethalin into your herbicide plan for 2018, talk to your PCA, or give one of the UCCE Rice Advisors a call. Especially for growers that have herbicide resistant grasses, it can be a valuable tool in reducing grass populations.
Over the past year, weedy rice has become a top issue in California rice, both for individual growers and for the industry as a whole. Working together, the University of California Cooperative Extension and the California Rice Commission have come up with a set of tools to assist in getting control of this pest. Of course, none of it would be possible without the input and cooperation of the Pest Control Advisers (PCAs) and California rice growers, who are the first line of defense in dealing with weedy rice. Additional assistance in material development and funding have come from the California Rice Research Board, the California Crop Improvement Association and the staff at the California Rice Experiment Station.
A new website, www.caweedyrice.com, contains all of the most up-to-date information regarding weedy rice in California. The website covers identification, management, and weedy rice sample submission.
An identification pamphlet was mailed out by the California Rice Commission a couple of weeks ago to most growers and PCAs. If you need additional pamphlets, they are available at your local UCCE office. Identification posters will be distributed to Agriculture Commissioner's offices, PCA offices, and rice mills and distributors in each county in the next few weeks. They are also available at your local UCCE office upon request.
The "Weedy Rice Reporter" app will let you send up to six pictures and aGPS location taken with your phone toUCCE RiceAdvisors so that we can confirm or rule out weedy rice. OnlyUCCE RiceAdvisors will be able to access any app submissions. We hope that the app will help us identify infestations early so that management actions can be implemented to eliminate weedy rice from the fields.
I went out on a few farm calls in the past week, and have noticed a trend. Due to the unusually wet weather this spring, some of the weeds are already producing seed out in the field! This occurs when the field was moist or wet in the spring, and was not tilled or sprayed prior to planting.
If you have weeds that are already setting seed, follow the steps below:
1) First, make sure to get proper identification of the weed species. Some weed species will produce seed and that seed can germinate and send up a second flush of weeds, in the same season! They are:
- Smallflower umbrella sedge
- Mexican sprangletop
NOTE: There are two types of sprangletop: Mexican and Bearded. Only the Mexican sprangletop will set seed that will germinate this season. Bearded sprangletop seed is dormant and won't germinate until the 2018 season.
2) If you have one of the above-listed species that is already setting seed, it is important to make sure that your follow-up herbicide application will control this second flush of germinating seeds. Otherwise, the amount of seed produced and deposited into the seedbank will be exponentially higher than in a normal year, because there will be two generations of plants that set seed in the same season!
3) If you have a weed species setting seed that is NOT listed above, you will likely not be able to do much this year, as the weeds are likely too large to control with herbicide and any impacts on yield have already occurred. Plan to have an aggressive program for next year (2018)!
BUTTE®, a rice herbicide, has received federal registration in the USA as well as state registration in California. It will be available to California rice growers for the upcoming 2017 season. Gowan Company, along with SDS Biotech and Nissan have collaborated to bring this product to California rice growers.
BUTTE® is a granular into-the-water herbicide that combines two modes of action: an HPPD-inhibitor (benzobicyclon), and an ALS-inhibitor (halosulfuron). It is the first HPPD-inhibitor available to California rice growers. Since weeds in CA rice have widespread herbicide resistance, BUTTE® offers a new option for resistance management for affected growers, particularly those with herbicide resistant sedges.
BUTTE® offers excellent control of many sedges, broadleaves and grasses. For a complete list of weeds controlled and suppressed, please refer to the herbicide label. BUTTE® is applied early in the season, and requires a 20-day water hold period. As always, growers and applicators should follow all label requirements, to ensure the best weed control, and to prevent the development of resistance.
There will only be enough product available for 2017 to treat approximately 50,000 acres, so growers interested in purchasing BUTTE® this season should talk to their Pest Control Adviser and the retail location where they normally purchase rice pesticides.
The University of California Davis Weed Science Program has been working with Gowan to research BUTTE® over the last several years. Studies on the weed control spectrum and timing began with Dr. Albert Fischer's program, and research on rates and formulations have continued under Dr. Kassim Al-Khatib. The UC Weed Program will continue to look at herbicide combinations that best compliment BUTTE® this year. The trials will be available for viewing at the 2017 Rice Field Day.
- Author: Kathy Keatley Garvey
Dr. Godfrey was internationally acclaimed for his research on rice and cotton. He was heavily involved in developing IPM to maintain the sustainability of California agriculture, seeking “to reduce the ‘footprint' of agriculture on the environment and society, and to advance the science of entomology and applied insect ecology.”
At UC Davis, he taught arthropod pest management and agricultural entomology. He developed IPM strategies for not only rice and cotton but for such field and vegetable crops as alfalfa, dry beans, timothy grass, melons, mint and onions.
A member of the entomology department since April 1991, Dr. Godfrey served as its vice chair in 2008, and also that year, as president of the Pacific Branch, Entomological Society of America.
“Larry was an outstanding contributor to the department, not only as a researcher and teacher, but also in the effective ways that he connected with clientele through outreach,” said Steve Nadler, professor and chair of the UC Davis Department of Entomology and Nematology. “He was a member of our department's Executive Committee and I could always count on Larry for sound advice.”
“Being the two Davis faculty with agricultural entomology extension duties, Larry and I shared a lot over the last 25 years and he was my closest colleague in our department when he passed today,” said Extension entomologist and distinguished professor Frank Zalom, an IPM specialist and a past president of the Entomological Society of America. “I've always respected him for being quiet and humble despite his many accomplishments. He filled the shoes of several faculty members who retired before he came to Davis and he did his job exceptionally well. It's hard for me to imagine not having him nearby as the go-to entomologist for field crops, although his research, extension, and, most importantly his graduate students, will serve as his legacy for years to come.”
Said professor Jay Rosenheim: “Larry was a researcher who always placed the farmer's needs first. This is why he was so highly valued by California's growers of rice, alfalfa, cotton, and vegetable crops, and why his research program grew and grew over his years at Davis. He was also an excellent communicator, and epitomized the role of researcher/educator in the Land-Grant system. Despite his illness, he continued to work tirelessly on his pest management research, refusing to compromise on his commitments. His dedication to our profession was truly remarkable.”
Yolo County Farm Advisor Rachael Long, who collaborated with Dr. Godfrey on dry bean research, said: “He was an incredibly dedicated field crop entomologist and terrific colleague with team spirit, and his loss leaves a big hole in our lives and I'll miss him.”
“What I admired about Larry was his stoicism,” said former graduate student Mohammad-Amir Aghaee, now a postdoctoral fellow at North Carolina State University. “Nothing seemed to wear down his resolve.”
Dr. Godfrey, born July 7, 1956, grew up on an Indiana farm. He received two entomology degrees from Purdue University, West Layfayette: his bachelor's degree in 1978 and his master's degree in 1980. He earned his doctorate in entomology in 1984 from the University of Kentucky, Lexington, studying with major professor Kenneth Yeargan. He was a member of Phi Beta Kappa, Phi Kappa Phi, Sigma Xi and Gamma Sigma Delta.
Said Yeargan: "As I stated in my letter of recommendation for Larry many years ago when he applied for the position at UC Davis, Larry was an outstanding 'synthesizer' of information. He had a knack for looking at a problem, thinking through all the ramifications, and coming up with logical, practical ways to approach the problem – and usually finding a solution. He will be missed by many." It was at the University of Kentucky where Larry met his wife-to-be, Kris, then a postdoctoral scholar.
Dr. Godfrey began his career as a product development specialist for Union Carbide Agricultural Products Co., Inc., Research Triangle, N.C., before joining the University of Nebraska's Department of Entomology from July 1987 to March 1991 as a research associate.
“Growing up on a farm in Indiana, I saw first-hand the ‘battles' that farmers and homeowners face trying to produce crops and grow landscape plants in competition with insects,” Dr. Godfrey recalled in an earlier interview. “I became fascinated with insects through the typical ‘bug-in-a-jar' hobby. A county Natural Resources Field Day cultivated my interest in entomology and this led to enrollment in the 4-H entomology project. By the time I was several years into the 4-H project, I was transporting a dozen wooden collection boxes full of pinned insects to the county fair.”
“My first summer job involved surveying for Japanese beetles as they progressed across Indiana. This was an invasive insect in the Midwest in the mid-1970s; this same insect is of serious concern now in California an invasive pest that could damage many crops—such as grapes—and ornamentals—such as roses.”
Dr. Godfrey was one of 24 founding members of the California Invasive Species Advisory Committee, appointed by then Secretary A.G. Kawamura of the California Department of Food and Agriculture, to recommend “ways to mitigate non-native species' effects on resources throughout the state.” The goal: to protect California's environment, food systems, human health and economy from invasive and destructive pests, plants and diseases.
At UC Davis, Dr. Godfrey zeroed in on invasive insect and mite pests such as silverleaf whitefly, panicle rice mite, and rice water weevil. In addition, he targeted scores of pests, including alfalfa weevils, blue alfalfa aphids, spotted cucumber beetles, and two-spotted spider mites. He researched plant response to insect injury, refining economic thresholds.He also researched various pest management tactics, including biological control, reduced risk insecticides, mating disruption, cultural control, and host plant resistance.
Highly respected by his peers, Dr. Godfrey received the Excellence in IPM Award in 2005 from the Pacific Branch, Entomological Society of America (PBESA), followed by the PBESA Distinguished Achievement Award in Extension in 2010. Nationally, he was elected chair of ESA's Section F (crop protection) in 2002.
For many years, he served as the advisor to the UC Davis Linnaean Games teams, which won regional (PBESA) and national (ESA) championships in college-bowl type competitions involving insect questions. He himself was on the championship 1983 University of Kentucky team, the second annual Linnaean Games in the North Central Branch of ESA “where it all started,” he said. “It was a few years before the other branches started this competition and several years before they did it at the national meeting.”
As part of his Extension work, Dr. Godfrey wrote publications, regularly met with growers, and delivered scientific talks at workshops. He addressed the annual California Rice Field Day for 25 years and also spoke at alfalfa IPM workshops, among others. He was a subject editor for the Journal of Cotton Science and the Journal of Integrated Pest Management. In addition, Dr. Godfrey served on many departmental, college and UC Agriculture and Natural Resources committees.
Funeral services will be held Saturday, April 29 in Salem, Ind. In lieu of flowers, the family asks for donations to pet rescue groups or groups that support young people interested in entomology or agriculture. A memorial and celebration of his life will take place at UC Davis in the near future.