- Author: Kathy Keatley Garvey
UC Davis entomology doctoral student Stacy Hishinuma has received and accepted a position in the USDA Pathways Internship Program with the Region 5 field office of the USDA Forest Service, San Bernardino.
Hishinuma studies the walnut twig beetle, Pityophthorus juglandis, which in association with a newly described fungus, Geosmithia morbida, causes thousand cankers disease (TCD) of walnut and butternut trees.
The walnut twig beetle is believed to be native to Arizona, California, New Mexico and Mexico. In 2006, plant pathologist Ned Tisserat and entomologist Whitney Cranshaw of Colorado State University identified the pathogen in declining black walnut trees in central Colorado. The disease has now spread east of the Mississippi to states in the heart of the valuable black walnut timberlands. Most recently it was reported from Indiana. Latest collection records show that the beetle and pathogen are now known from nine states in the western United States and seven states in the eastern USA. In 2013 the disease was also reported in Italy marking the first time that it occurred in Europe.
Hishinuma works with major professor Mary Louise Flint and is co-advised by chemical ecologist and forest entomologist Steve Seybold of the Pacific Southwest Research Station, USDA Forest Service, Davis, an affiliate of the department. Flint is an Extension specialist emeritus with the UC Davis Department of Entomology and Nematology and a former associate director with the UC Integrated Pest Management Program.
“USDA will provide some financial support during the end stages of her Ph.D. thesis, in exchange for 320-640 hours of work and training over the next 14 months,” said Seybold. Then, in June 2016 her position will be converted to that of a permanent entomologist with the USDA Forest Service office in San Bernardino after she has completed her thesis. She will be responsible for forest insect survey, detection, and management on four national forests in southern California ranging from San Diego to Monterey counties.
“The highly competitive internship and guaranteed position are a credit to her and her achievements,” Seybold said.
Seybold and Flint assisted her in developing the internship, as did Richard “Rick” Bostock, UC Davis professor of plant pathology.
Hishinuma won the 2013 Western Forest Insect Work Conference Memorial Scholarship for her research on TCD and presented her work at group's 65th annual conference, held March 31-April 3, 2014 in Sacramento. She also received two scholarships from the California Garden Clubs, Inc. (CGCI) and a McBeth Memorial Scholarship to support her research on TCD.
Seybold's research group has led the effort to characterize the disease in California and to develop a nationwide detection program for the beetle. They recently published two papers in the journal PLOS ONE that characterize the genetic diversity and invasion patterns of both the pathogenic fungus and the beetle in the United States. Scientists believe that TCD occurs only on walnut, butternut, and wingnut, but it is most damaging to native black walnuts, Juglans californica, J. hindsii, and J. nigra although the disease has been recorded on at least 10 species of walnuts or their hybrids in California. Often the first symptoms of TCD are flagging and yellowing leaves and branch dieback, Seybold said. Affected branches show sap staining and pinhole-sized beetle holes. Beneath the surface are dark stains caused by the funguhe news is startling, but not totally unexpected.
- Author: Kathy Keatley Garvey
His daughter-in-law, Mary Louise “Mary Lou” Flint, a longtime leader of the University of California Statewide Integrated Pest Management (UC IPM) Program and a newly retired Extension entomologist with the UC Davis Department of Entomology and Nematology, will be honored at a dinner on Dec. 1 as the recipient of the 2014 James H. Meyer Distinguished Achievement Award for her outstanding contributions to the university.
The event will take place at 6 p.m., in Ballrooms B and C of the UC Davis Conference Center. Reservations may be made by contacting UC Davis Special Events at (530) 754-2262 by Nov. 24.
Flint, UC IPM's associate director for Urban and Community IPM, and who retired at the end of June, is the third entomologist (Frank Zalom, 2004, and Thomas Leigh, 1988) to receive the Academic Federation award, first presented in 1971.
Her father-in-law, who served as chancellor from 1969 to 1987, during the university's greatest period of growth and change, strongly supported the Academic Federation and the Cooperative Extension Specialists, Agricultural Experiment Station researchers and other non-Senate academics it represents, Flint said.
Parrella said that Flint “has been heavily involved in the leadership, creativity and the success of UC IPM Program since 1983 and is UC IPM's longest-tenured employee. Also since 1983, she has served as an Extension entomologist in our department and we are proud of her innovative ideas, dedication, commitment and accomplishments. Dr. Flint is truly an outstanding leader and visionary who has initiated, conducted and established research, educational and outreach programs that we sometimes take for granted. She advances IPM practices that are economical, environmentally friendly and health conscious.”
Wrote UC IPM Director Kassim Al-Khatib: “Dr. Flint has initiated, conducted, and established an outstanding and well respected IPM research and outreach program for urban and community. Many of her programs and findings have significant impact on pest management in California. She is a talented, capable specialist and good communicator to the IPM end-user.” Globally, the UC IPM program is considered the gold standard of IPM.
Flint received her bachelor's degree in plant sciences in 1972 from UC Davis, and her doctorate in entomology from UC Berkeley in 1979. “We are fortunate that she chose to spend her career here at UC Davis,” Parrella said.
Among her accomplishments:
- Created, wrote or edited and oversaw the development of the UC IPM's IPM Manual series of books from 1980-2007; this series includes IPM manuals on 15 different agricultural crops or crop groups. More than 100,000 copies of these books have been sold worldwide.
- Oversaw the development and creation of the online UC IPM Pest Management Guidelines from 1987-2007. This series included 43-crop specific PMGs featuring hundreds of pests and thousands of photographs and authored by UC experts around the state and updated regularly. Flint served as technical editor. She developed many online tools associated with the PMGs such as the Natural Enemies Gallery and the Weed Galleries.
- Established the UC IPM Pest Note series for home, garden, landscape and urban audiences. This series covers more than 165 pests. About 12,000 people a day access these publications on the UC IPM Home and Garden website.
- Authored several important books on IPM including Pests of the Garden and Small Farm, IPM in Practice: Principles and Methods of IPM and The Natural Enemies Handbook. She developed the Pesticide Compendium series along with Patrick O'Connor Marer.
- Created some of the earliest interactive learning tools of IPM, including the 1996 CD-ROM Solving Garden Problems: A University of California Interactive Guide and The UC Interactive Tutorial for Biological Control of Insects and Mites (an interactive CD-ROM, Publication 3412). She and her colleagues also created some of the first online training materials for IPM with online training programs for retail nursery and garden center personnel. The UC Guide to Healthy Lawns on the UC IPM website is another key accomplishment. UC IPM takes its 16 portable UC IPM Touch Screen IPM kiosks to hundreds of retail stores and community events. More recently, Flint has been heavily involved in creating YouTube videos on the UC IPM channel and disseminating information through other electronic and social media.
- Developed hands-on, train-the-trainer programs for UC Master Gardeners, retail nursery personnel and landscape professionals that have resulted in the delivery of information to far more people than would be possible through conventional training meetings. Among the topics: biological control, pesticides and landscape pest identificatio
Lately Flint has been involved with the thousand cankers disease, caused by the walnut twig beetle, Pityophthorus juglandis, in association with the fungus, Geosmithia morbida. The disease kills walnut trees, especially black walnuts. She continues to work on the project with research entomologist Steven J. Seybold of the USDA Forest Service, Pacific Southwest Research Station, Davis, and other scientists.
Seybold, an affiliate of the UC Davis Department of Entomology and Nematology, said that on a national level, Flint was "instrumental in facilitating the rapid processing and release of the national trapping guidelines for the walnut twig beetle."
"Once our team had discovered the aggregation pheromone of this beetle and had demonstrated its value in trapping the insect in California, Mary Louise assisted us with the preparation and dissemination of useful trapping guidelines, which have been employed by state pest regulatory officials and detection entomologists throughout the country.”
Widely honored by her peers, Flint received the 2002 Outstanding Lifetime Achievement Award for Integrated Pest Management from the Association of Applied IPM Ecologists; a 2003 IPM Innovator Award from the California Department of Pesticide Regulation as part of the Sacramento Water Wise Pest Control Program; a 2003 resolution from the Sacramento City Council honoring her for contributions to the Sacramento Water Wise Program; a 2004 Environmental Services Award from the San Francisco Department of the Environment; and an international IPM Award of Recognition, “Grower Incentives Team Project,” at the 2009 International IPM Symposium in Portland, Ore.
Flint is not only the third entomologist to receive the award, but the third IPM specialist. Frank Zalom, a distinguished professor in the UC Davis Department of Entomology and Nematology, directed the UC IPM Program for 16 years (1988-2001). He is currently serving as president of the 7000-member Entomological Society of America. Thomas Leigh (1923-1993) stood at the forefront of integrated pest management of cotton pests, according to an article in the summer 1994 edition of American Entomologist. He taught courses on cotton IPM and host plant resistance.
- Author: Kathy Keatley Garvey
That's when butterfly expert Art Shapiro, professor of evolution and ecology at UC Davis, will be speak at the Northern California Entomology Society meeting, to be held at the Harry H. Laidlaw Jr. Honey Bee Research Facility on Bee Biology Road, UC Davis.
The meeting will begin at 9:15 a.m. with registration for club members and guests, and conclude at approximately 2:30 p.m. The group, which meets three times a year, is comprised of university faculty, researchers, pest abatement professionals, students and other interested persons.
Shapiro will lead off the program at 9:45 a.m. with his talk on “History of the Sacramento Valley Butterfly Fauna.” A noted butterfly expert, he has monitored butterflies for more than 35 years in the Central Valley and maintains Art's Butterfly World website.
Chemical ecologist Steve Seybold of the USDA Forest Service, Davis, and an affiliate of the UC Davis Department of Entomology, will speak on “Goldspotted Oak Borer in California” at 10:30 a.m.
Following the lunch from noon to 1 p.m., Jason Leathers of Pest Detection/Emergency Projects, California Department of Food and Agriculture (CDFA), will cover “Pest Control Approaches and Evaluations on Success of 2012 Insect Eradication Programs in California.”
At 1:45 p.m., Stephen Brown, CDFA, and Anthony Jackson, Animal and Plant Health Inspection Service (APHIS), USDA, will discuss “California and Federal Regulations Concerning Importing Living Plant Pests.”
The society meets three times a year: the first Thursday of February at the California Department of Food and Agriculture (CDFA), Sacramento; the first Thursday of May, at the Harry H. Laidlaw Jr. Honey Bee Research Facility, UC Davis; and the first Thursday of November in the Contra Costa Mosquito and Vector Control District conference room, Concord.
Membership is open to the public; dues are only $10 year. President is Robert Dowell, a staff environmental scientist at CDFA.
More information about the meeting is available from Extension apiculturist Eric Mussen of the UC Davis Department of Entomology. Serving as the society’s treasurer, he can be reached at ecmussen@ucdavis.edu or by (530) 752-0472.
- Author: Kathy Keatley Garvey
No wonder. The insect, measuring about 1.5 millimeters long, is much smaller than a grain of rice.
Now, however, they can see a teddy-bear-sized version, thanks to a University of California, Davis entomology major Kristina Tatiossian, a member of the Research Scholars Program in Insect Biology.
Through the UC Davis Art/Science Fusion Program, Tatiossian, a junior, crafted a ceramic mosaic sculpture of the tiny walnut twig beetle for her research poster, “Flight Response of the Walnut Twig Beetle, Pityophthorus juglandis, to Aggregation Pheromones Produced by Low Densities of Males.”
The beetle jutting from the poster is so true to form that scientists studying the insect not only readily recognize it, but point out that it’s a female. That includes her mentor, chemical ecologist and forest entomologist Steve Seybold of the Davis-based Pacific Southwest Research Station, USDA Forest Service, and an affiliate of the UC Davis Department of Entomology.
Seybold and Andrew Graves, a former UC Davis researcher with the UC Davis Department of Plant Pathology, who now works for the USDA Forest Service, first detected the newly recognized beetle-fungus disease, known as Thousand Cankers Disease (TCD), in California in 2008. TCD had been detected earlier in Colorado and its impact had been noted even earlier in New Mexico, Oregon, and Utah. TCD and its history are chronicled in a newly revised “Pest Alert” issued by the USDA Forest Service.
Tatiossian accomplished the research project as part of the Research Scholars Program in Insect Biology, which aims to provide undergraduates with a closely mentored research experience in biology. Headed by professor Jay Rosenheim, and assistant professor Louie Yang of the UC Davis Department of Entomology, the program currently has 12 students; students apply when they are freshmen, sophomores or transfer students. Tatiossian joined the program in 2011 and is mentored by Steve Seybold.
Tatiossian completed the ceramic mosaic project over a four-week period. She earlier worked on two UC Davis Art/Science Fusion Program projects, including the “Tree of Life,” with the program’s founders, entomologist/artist Diane Ullman and artist Donna Billick. A former Los Angeles resident, Tatiossian will receive her bachelor’s degree in entomology this June and then plans to attend graduate school to study either biochemistry or virology.
Tatiossian will giving an oral presentation on her research at the Pacific Branch, ESA meeting, set for April 7-10 at South Lake Tahoe. Then she will display the poster again in the Undergraduate Research Conference at UC Davis on April 24 in Wellman Hall.
By itself, the beetle, native to Arizona, California, New Mexico and Mexico, does little or no damage. But when coupled with the newly described fungus, Geosmithia morbida, it is killing thousands of walnut trees.
The disease is creating havoc throughout much of the western United States, Seybold said, and is now heading east. Its primary host is the black walnut tree but it also attacks other walnut trees.
“Male WTB initiate new galleries and produce an aggregation pheromone, which can be used to study patterns of initial host colonization behavior of WTB. It has been previously shown by Graves and colleagues (2010) that as the number of males in a branch is increased from 20 to 200, the flight response of males and females is similarly increased,” she wrote. “We investigated flight responses to lower numbers of males in cut branch sections of northern California black walnut, Juglans hindsii.”
Her objective: “To determine the minimum number of males in an artificially infested branch of Juglans hindsii necessary to elicit a flight response from WTB.” She found that as little as one to five males is enough to elicit the aggregation response at her field study sites at two locations in Davis.
The poster will be displayed on the third floor of Briggs Hall, just outside the Department of Entomology’s administration office.
On her poster, Tatiossian credits Seybold; Extension entomologist Mary Louise Flint, associate director for Urban and Community IPM, UC Statewide Integrated Pest Program; entomology graduate student Stacy Hishinuma, and postdoctoral researcher Yigen Chen of the UC Davis Department of Entomology.
And the UC Davis Art/Science Fusion Program where the tiny walnut twig beetle sprang to life.
- Author: Kathy Keatley Garvey
Chemical ecologist and forest entomologist of Steve Seybold of the USDA Forest Service, Pacific Southwest Research Station, Davis, Calif., and a faculty affiliate of the UC Davis Department of Entomology, is leading a research group to characterize the disease in California.
A new member of the team is UC Davis entomology graduate student Stacy Hishinuma (right), who just received a McBeth Memorial Scholarship to help fund her research.
TCD is caused by the walnut twig beetle, Pityopthorus juglandis, in association with a newly described fungus, Geosmithia morbida.
“The beetle is believed to be native to Arizona, California, New Mexico and Mexico,” Hishinuma said, “but was never associated with walnut tree mortality until just recently.”
The disease was first noticed in canker-riddled black walnuts in Utah and Oregon in the early 1990s, but scientists attributed that to environmental stress. In 2006, plant pathologist Ned Tisserat and entomologist Whitney Cranshaw of Colorado State University identified the pathogen in declining black walnut trees in central Colorado. TCD is now found in eight western states (Arizona, California, Colorado, Idaho, New Mexico, Oregon, Utah and Washington), plus Tennessee.
“My project focuses on understanding more about the biology of the beetle and fungus and documenting the frequency and progression of TCD in various walnut species throughout California,” Hishinuma said. “The McBeth scholarship is funding my travel to field sites across California.”
Hishinuma, who is seeking her master’s degree in entomology, works with major professor and integrated pest management (IPM) specialist Mary Lou Flint and is co-advised by Seybold. Flint, with the statewide UC IPM Program, is the associate director for urban and community IPM, and a Department of Entomology extension specialist.
The fungus enters the tree when the beetle tunnels into the bark to prepare egg galleries. “The fungus is probably carried as conidia on the beetle’s elytra or wing covers,” said Seybold, who has been studying the chemical ecology and behavior of bark beetles for more than 25 years.
Scientists believe that TCD occurs only on walnut, predominantly native black walnut, Juglans californica and J. hindsii, although the disease has been recorded on 10 species of walnuts or their hybrids in California. Often the first symptoms of TCD are flagging and yellowing leaves and branch dieback, Seybold said. Affected branches show sap staining and pinhole-sized beetle holes. Beneath the surface are dark stains caused by the fungus.
A tree can survive the stress produced by a few cankers, but when high populations of the beetle enter the tree and the numerous small cankers coalesce, the disease girdles twigs and branches. Eventually TCD attacks the main stem of the weakened tree down to the soil line.
Last summer, a USDA/UC Davis research team began tracking the pathogen and the beetle throughout the state, particularly in commercial orchards.
To prevent spread, infected trees should be removed and destroyed immediately by grinding or burning to ensure that beetles are destroyed, Seybold said. Infested walnut for chips, firewood, or woodworking should not be moved to new areas. Possible detections can be reported to the local agricultural commissioner’s office or to the local UC Cooperative Extension office.
Hishinuma, from Burbank, completed her undergraduate work at UC Davis in animal biology, with an entomology emphasis. She began her graduate studies this fall after working for a year in southern California assisting with research on the goldspotted oak borer, a relatively new pest in southern California that kills oak trees. Beetle-infested firewood contributes to the problem, as it does with thousand cankers disease.
The McBeth Memorial Scholarship was established in 1986 by Barbara McBeth Woodruff (1924-2007) in honor of her parents, Ira Guy McBeth and Rose McBeth, and her sister Frances McBeth Black. Ira Guy McBeth, an entomologist who received his doctorate from the University of California in 1915, made notable contributions to the citrus industry and served as an executive in agricultural, chemical and development companies.
Meanwhile, a thousand questions about thousand cankers disease...and maybe soon...solutions.
Related Links:
Steve Seybold discussed thousand cankers disease in a seminar presented May 19, 2010 to the UC Davis Department of Entomology. The seminar was webcast and is archived on the entomology website. (USDA Forest Service Pest Alert on Thousand Cankers Disease of Walnut (targeting eastern U.S. region). (May 2010)
UC IPM website (Authors: Andrew Graves, postdoctoral researcher, formerly with the UC Davis Department of Plant Pathology; Mary Louise Flint, UC IPM Program and Department of Entomology, UC Davis; Tom Coleman, USDA Forest Service, Forest Health Protection, San Bernardino; and Steven Seybold, USDA Forest Service, Pacific Southwest Research Station, Davis)
Detected in Tennessee (News release, Aug. 9, 2010, UC Davis Department of Entomology website)
Detected in California (News release, July 2, 2010, UC Davis Department of Entomology website)