- Author: Whitney Brim-DeForest
- Author: Sean Hogan
- Author: Luis Espino
For the past several years, California rice has been dealing with a pesky new weed, weedy rice, aka “red” rice. Weedy rice is a difficult pest to manage, because it is the same species as rice (both are Oryza sativa L.), rendering herbicide use next-to-impossible. In the southern U.S, rice-growing region (Texas, Louisiana, Mississippi, Missouri, Arkansas), they utilize two rice varieties (in rotation) that have been conventionally bred to tolerate the use of two herbicides: Clearfield (imazamox) and Provisia (quizalofop). Since weedy rice is susceptible to these chemicals, the entire field can be sprayed with these herbicides: the rice varieties survive, and the weedy rice is controlled. In California, these varieties are not available, so rice scientists here have been working on registering and applying spot-spray herbicides (no herbicides are currently registered for spot-spraying weedy rice in California rice).
Why drones?
Most of the weedy rice in California is found in small patches, or as individual plants, sprinkled throughout fields. Using a hand-held spot sprayer to spray individual plants in large fields (200 acres or more) is a lot of work, and also involves having a trained applicator that can identify weedy rice in the field. Using a drone to spray the individual plants would be a lot more efficient. Dr. Ken Giles, professor emeritus at UC Davis, is currently working on the spray technology aspect, and has made progress in being able to spray individual plants in a rice field (Giles, 2017). In order for the spray drone to work, however, it needs a map to follow so it “knows” where to spray. That is where the second part of the research comes in - can we map weedy rice?
Is it possible?
Mapping weedy rice in the field involves having a camera attached to a drone that can “see” the weedy rice in the field, and differentiate it from all of the other plants found in the field, namely the rice variety, and the other weed species. When we first began this research, we had many doubts. Weedy rice and rice are the same exact species, after all, and it seemed unlikely that we could find a camera to that had this capability.
In 2018, we ran a preliminary drone flight in one field known to have weedy rice. We had two cameras, one a red-green-blue (RGB) camera, and one a multispectral (blue-green-red-red edge, and near infrared) camera. The positions of weedy rice and the rice variety were ground-truthed using a handheld GPS. When the data was analyzed, the weedy rice was not discernible from the rice in both the RGB and multispectral camera analysis.
In 2019, we ran two additional drone flights, this time angling the cameras at a 90-degree oblique angle, instead of straight down on the fields from above. We also ran an analysis using an Analytical Spectral Devices (ASD) hyperspectral electrospectrometer to collect spectral signatures from all of the plants in the greenhouse (weedy rice, rice and all major grass weed species). Unfortunately, once again, the results from the flights did not show discernable differences between the weedy rice and rice. The results from the ASD also showed small differences between the weedy rice, the rice variety and the weed species. However, the spectra the camera sees are currently not the ones where there are spectral differences between the plants.
Research outlook
So, is it possible to map weedy rice? It might be. Currently available cameras may not be able to “see” the spectral signatures of the plants. Sean Hogan, with the UCANR Informatics and GIS (IGIS) Statewide Program, will continue to analyze the 2019 data, and if it appears promising, we may fly again this year with a different camera. Look for an update in 2020!
This article was originally published in the UC Weed Science blog.
- Author: Jeannette Warnert
- Author: Pamela Kan-Rice
People from across California and around the world got to taste new crops, see research demonstrations and learn about several UC ANR activities at the World Ag Expo Feb. 12-14. Despite the cold rainy weather, the world's largest agricultural exposition attracted 102,878 people representing 48 states, the District of Columbia and 65 countries to Tulare.
At an outdoor tent, Beth Grafton-Cardwell, UC Cooperative Extension specialist, Greg Douhan, UCCE citrus advisor, and other researchers, handed visitors fresh Tango citrus grown at the Lindcove Research and Extension Center and told them about their citrus variety research.
Ruth Dahlquist-Willard, UCCE small farms advisor, and Michael Yang, small farms and specialty crops agricultural assistant, encouraged visitors to taste moringa tea. Surendra Dara, UCCE entomology and biologicals advisor, described how Bagrada bugs and other pests under the microscopes can be controlled by microbes. Roger Baldwin, UCCE wildlife specialist, and Niamh Quinn, UCCE urban wildlife conflict advisor, took turns showing taxidermy vertebrate pests and describing their management research.
Jeff Mitchell, UCCE specialist, and Jeff Dahlberg, Kearney Agricultural Research and Extension Center director, gave demonstrations to show the superior health of soils managed with conservation techniques.
Demonstrating the use of high-tech in agriculture, Sean Hogan, Informatics and Geographic Information System academic coordinator, Andy Lyons, IGIS program coordinator, and Jacob Flanagan, IGIS programmer, showed how they use drones and cameras in agricultural research.
Inside Pavilion A, Teresa Rios-Spicer, UCCE nutrition program manager, andYeseniaMedrano, UCCE community education specialist, both from Tulare County, challenged visitors to test their nutrition knowledge by playing Jeopardy! Visitors could spin the UC Master Gardeners prize wheel to answer gardening questions and win seeds. 4-H members invited youth to peer into virtual reality goggles to give them an idea about the fun activities that can be part of joining 4-H.
Frank Mitloehner, UC Cooperative Extension specialist, gave a seminar explaining confusion in the media about the amount of greenhouse gas livestock emit in California and globally. He reviewed the innovations in livestock production that are leading the way to a "greener future" for California and U.S. agriculture.
Beth Grafton-Cardwell, UC Cooperative Extension citrus entomology specialist, and Victoria Hornbaker of the California Department of Food and Agriculture, gave an update on regulatory protocols relating to Asian citrus psyllid and HLB quarantines and the proper transportation of bulk citrus to prevent the spread of the pest and disease.
The California and Dutch AgFoodTech innovation partners reunited in Tulare for a networking luncheon to share their action plan with invited guests and scope the projects.
- Author: Pamela Kan-Rice
UC ANR had a major presence at World Ag Expo Feb. 13-15 in Tulare. In addition to exhibits inside the Pavilion, this year, UC ANR hosted a series of well-attended researcher demonstrations of citrus varieties, soil quality and other subjects in a tent outside. UC ANR scientists also gave presentations on “hot topics” ranging from the use of drones and other electronic technology in production agriculture to animal health to human nutrition.
“Between our tent and our Pavilion space, there's been a lot of very good engagement and discussions with the primary stakeholder audience,” said Mike Janes, Strategic Communications director.
On the opening day of the expo, USDA Secretary Sonny Perdue held a town hall to hear from members of California's agriculture industry concerns about the upcoming Farm Bill. VP Glenda Humiston was among those present for the discussion, which attracted considerable media attention.
Western Farm Press wrote: “While trade, labor and regulatory issues may top the list of agricultural policy issues Perdue faces in Washington D.C., Glenda Humiston, Vice President of the University of California Agriculture and Natural Resources Division of the state's Land Grant university, stressed the importance of adequate research funding and federal definitions of rural versus urban, which she said is having detrimental impacts across California on important program funding.”
“If a county has one town that has 50,000 population in it, the entire county is labeled metropolitan for purposes of allocating funding,” Humiston said in the Hanford Sentinel.
“Humiston said that while UCANR has a ‘proud tradition of research in California,' the university is plagued by reduced budgets at the same time the state is plagued by a new invasive pest every several weeks. She said for the university to stay ahead of these issues and to help growers in these and many other areas, additional funding is vital,” Farm Press reporter Todd Fitchette wrote.
In private communication, Fitchette said that widespread applause broke out from the audience in response to Humiston's comments.
- Author: Pamela Kan-Rice
Hogan visits Capitol Hill
In early April, Sean Hogan, academic coordinator II for Informatics and Geographic Information Systems, presented at the AmericaView Winter Business Meeting, in Reston, Va., as representative of the CaliforniaView section of the consortium of remote sensing scientists. Hogan spoke about some of the ways that UC ANR is using drones to advance environmental and agricultural research. While he was near Washington D.C., Hogan went to Capitol Hill to meet with Congressman Ami Bera, Congressman Paul Cook and staffers for Senator Diane Feinstein.
Read more in the IGIS blog http://ucanr.edu/blogs/blogcore/postdetail.cfm?postnum=23768.
Congressman Costa visits UC CalFresh class in Madera
When United States Congressman Jim Costa learned about the federally funded nutrition education programs being offered in his district, he made plans to visit.
He wanted a first-hand experience with UC CalFresh, in which UC Cooperative Extension educators visit classrooms to share new foods, teach healthy eating strategies and demonstrate physical activity to children and low-income families.
Read more in the Food blog http://ucanr.edu/?blogpost=23767&blogasset=91109
The Informatics and Geographic Information Systems (IGIS) Statewide Program will hold a three-day "Dronecamp" to be held July 25-27, 2017, in Davis. This bootcamp style workshop will provide "A to Z" training in using drones for research and resource management, including photogrammetry and remote sensing, safety and regulations, mission planning, flight operations (including 1/2 day of hands-on practice), data processing, analysis and visualization.
The workshop content will help participants prepare for the FAA Part 107 Remote Pilot exam. Participants will also hear about the latest technology and trends from researchers and industry representatives.
Dronecamp builds upon a series of workshops that have been developed by IGIS and Sean Hogan starting in 2016.
“Through these workshops and our experiences with drone research, we've learned that the ability to use mid-range drones as scientifically robust data collection platforms requires a proficiency in a diverse set of skills and knowledge that exceeds what can be covered in a traditional workshop,” said Hogan. “Dronecamp aims to cover all the bases, helping participants make a great leap forward in their own drone programs.”
Dronecamp is open to all, but will have a focus on applications in agriculture and natural resources. No experience is necessary. The number of seats is limited, so all interested participants must apply before they can register. Applications are due on April 15, 2017. For further information, please visit http://igis.ucanr.edu/dronecamp/.