- Author: Jeannette E. Warnert
California oak woodlands are highly prized ecoregions where stately trees, many of them hundreds of years old, are cornerstones of a habitat for wildlife and native plants. Sadly, some of these ecosystems are seriously threatened by exotic pests and diseases, encroachment by less desirable vegetation, and wildfire.
Each year, UC Cooperative Extension hosts workshops to share scientific developments aimed at conserving these important habitats – and the economic value of ranching – on oak woodlands, which are found on the lower elevation slopes of the Sierra Nevada, the Coast Range and other foothill areas of California.
Typically, the workshops are held in person and draw moderate-sized audiences for presentations, questions and answers, and field trips. Because of the COVID-19 pandemic, this year's workshop was offered online in April with pre-recorded presentations available for viewing at the participants' convenience and a live question-and-answer session on Zoom.
The retooled event garnered 500 registrants, over 300 views of the YouTube videos and 140 participants in the live Q&A session. The presentations and Q&A session are still available online for future viewing as well.
“People from all walks of life participated, including those with professional and personal interest in oak woodlands,” said Yana Valachovic, UCCE forest advisor in Humboldt and Del Norte counties and a conference organizer.
Presentations at the 2020 conference included the following topics:
Encroachment by Douglas-fir
In Northern California, the biodiversity of oak woodlands is being threatened by Douglas-fir encroachment. The oaks' shade helps the young conifers get established with protection from harsh sun. In time, the fast-growing Douglas-fir trees pierce the oak canopies and begin to crowd out the areas' native understories, which are important for the diversity of birds, mammals and reptiles attracted to oaks.
As the Douglas-fir continue to grow and multiply, they threaten the very lives of the oak trees and the unique ecosystem they dominate.
To better understand the Douglas-fir encroachment, Valachovic established 10 research sites in Humboldt and Mendocino counties to gather information about the fate and the age of oaks. She and her research partners determined the ages of the oaks and firs, and counted the seedlings, saplings, snags and understory vegetation.
“With this research, we were able to demonstrate that even though the oak trees can be smaller in diameter they are much older than the Douglas-fir trees,” Valachovic said. “The encroachment process is happening quickly, and the oaks are falling out of the system.”
The shift appears to have been initiated in the mid-19th and early-20th centuries, coinciding with the Gold Rush and wildfire suppression.
With the data confirming Douglas-fir encroachment, Valachovic turned her attention to oak woodland restoration. At 14 sites in Humboldt and Trinity counties, her team studied the effects of Douglas-fir removal.
“Grasses and forbs under the oaks reestablished. Diameter growth on the oaks increased,” she said.
These research findings contributed directly to changes in policy that had previously limited land owners' ability to remove and sell conifers encroaching on oak woodland. The research also helped create new funding opportunities to support oak woodland restoration and conservation in Northern California.
Case study of oak woodland wildfire recovery
In July 2018, about two-thirds of the 5,289-acre UC Hopland Research and Extension Center was burned by the River Fire.
The transformation of the land, which had likely been without a large wildland fire for at least 100 years, was intense and stressful, said UC Cooperative Extension forest advisor Michael Jones. However, it also provided a unique opportunity for researchers to compare the impact of wildfire on the resiliency of vegetation on grazed and ungrazed oak woodland.
Jones established 35 one-fifth acre research plots at the research center and collected data two months following the fire and one year later. The research will continue in the future to better understand long-term impacts, but Jones was able to share revealing early results at the workshop.
Right after the fire, in severely burned areas areas, the future of the oaks looked ominous. Jones predicted 40% tree mortality.
“The oaks were exposed to persistent, intense heat. They were cooked,” he said. “But two months after the fire, we were already seeing basal sprouts. This was an amazing response by the trees. Oaks are pretty damn tough.”
A year after the fire, surveys showed that tree mortality in the burned areas was 25%, much less than Jones' early predictions. While some management for specific situations in severely burned areas may be necessary – such as removal of hazard trees, reducing fuels in defensible spaces or removal to control invasive species – the results of this work show the trees recover naturally.
“Esthetically, I know these systems aren't as pleasing as they were before, but ecologically, they are healthy and recovering,” he said. “In 100 years, it will look just as good as before the fire.”
Fire impacts in woodland areas previously grazed and not grazed
The fire on the research station also permitted Jones to compare the fire's differing impact on non-grazed and grazed oak woodland. At first, the grazed areas looked almost unscathed with minimal flame scorching on the bark, while an area where the pasture hadn't been grazed for 25 years had evidence of much higher severity fire.
“Grazing is a phenomenal way to help manage fuels,” Jones said. However, the grazed areas displayed ecological shortcomings a year later.
“In grazed pastures, the large mature trees were still alive, but there was no oak regeneration (basal sprouting or seedlings),” Jones said. “In the ungrazed area, a lot of biomass had been killed, but there's nearly 100% resprout of oak trees and we have an impressive amount of oak seedling recruitment.”
Jones said he isn't discouraging grazing.
“But it is important to protect sites from grazing, and especially wildlife browse, when a landowner or land managers' objectives are to regenerate or conserve oak woodlands,” Jones said.
New ambrosia beetle another threat to California oaks
Akif Eskalen, UC Cooperative Extension specialist in the Department of Plant Pathology at UC Davis, has identified a new insect-fungus team that causes oak borer wilt in Northern California Valley and Blue Oaks. It is an ambrosia beetle, commonly known as Mediterranean Oak Borer, which carries several fungi in its mouth. The beetle bores into the tree and introduces fungi to grow for food. The fungi spreads and disturbs the transportation of water and nutrients, causing wilt in the tree.
The oozing and staining lesions on the bark are similar to other oak fungal diseases, such as Sudden Oak Death. The beetle – native of Mediterranean basin countries in Africa, Asia and Europe – cannot fly far, so most likely is transported for long distances on infested firewood.
During the workshop, Eskalen suggested not moving firewood, removing heavily infested trees and chipping infested wood into 1-inch particles to reduce the spread of the ambrosia beetle and its fungal partner. He asked viewers to report any suspected oak tree infestations to the local agricultural commissioner, CDFA Diagnostic Laboratories, UC Cooperative Extension advisors or CALFIRE. Chemical options for sparing oaks from the ambrosia beetles' devastation are under investigation.
Threats to oaks and other native plants from root rotting Phytophthora
Restoration plantings have inadvertently introduced plant pathogens to native oak woodland ecosystems in California, said Ted Swiecki of Phytosphere Research, an organization that provides consulting services related to natural resource management, horticulture, urban forestry, and agriculture. The group of pathogens causing the damage are largely from the Phytophthora genus, first described in the 1860s. The name translates from Greek to “plant destroyer.”
Swiecki has observed when Phytophthora infested plants and soils are introduced to native habitats, the pathogens can attack various native plants, including toyon, madrone, manzanita and full-grown oaks. Once established, the pathogen can spread along drainages, by moving soil from one area to another and by hitchhiking on equipment, tires and hiking boots.
The pathogen can easily be overlooked at nurseries, which, by their nature, have conditions that favor Phytophthora development. Plants at nurseries are well watered, have high root density and are often placed on the ground where they can pick up pathogens.
He said the best approach to tackling Phytophthora is not using nursery stock for restoration or beautification of natural oak woodland. Direct seeding, using natural regeneration, or onsite propagation are safer ways to enhance vegetation in oak woodland.
“It's easier to prevent Phytophthora from being introduced in the first place and much cheaper and more effective than trying to eradicate it later,” Siewcki said.
- Author: Pamela Kan-Rice
Emily Delk joined the Development Services team in August as the director of Annual Giving and Donor Stewardship Programs.
She brings fundraising and event planning experience from a broad background of nonprofit organizations including the Crocker Art Museum, Sutter Health, and Fairytale Town. Earlier this year, Delk was selected as one of 10 development professionals to compete for cash and in-kind support through a public-speaking program called Fast Pitch, where she earned high praise and won top prizes.
She holds a bachelor of fine arts degree in communications from Chapman University in Orange.
Delk is based at the ANR building in Davis and can be reached at (530) 750-1346 and email@example.com.
Akif Eskalen, a UC Cooperative Extension specialist whose research focuses on plant pathology at UC Riverside, has accepted a new position at UC Davis. He will be filling the position of his late mentor, Doug Gubler. From now on, he will work on grapes, strawberries, caneberries, blueberries and other tree fruits.
“Akif has been instrumental in bringing new light to the understanding of such basic disease problems as citrus twig and shoot dieback, citrus botryosphaeria branch canker, citrus dry root rot and ‘Fukumoto' foamy bark (http://eskalenlab.ucr.edu/citrusdiseases.html),” wrote Ben Faber, UCCE advisor in Ventura County, in the Topics for Subtropics blog. “He has cleared up the mysteries surrounding avocado black streak, dothiorella branch canker and avocado stem and leaf blight. His studies have also covered oak diseases that are exacerbated by invasive pests (http://eskalenlab.ucr.edu/handouts/oakwoodlandsdiseasesmanagement.pdf).”
Eskalen and John Kabashima, UCCE advisor emeritus, recently received the Award of Arboricultural Research from the Western Chapter International Society of Arboriculture, recognizing their research on the polyphagous shot hole borer, a beetle that is causing severe fusarium dieback damage to avocado and landscape trees in Southern California (http://eskalenlab.ucr.edu/pshb.html).
Eskalen can be reached at 267 Hutchison Hall at UC Davis and firstname.lastname@example.org.
Mark Hoddle and Richard Stouthamer have been elected 2018 fellows of the Entomological Society of America, the largest organization in the world serving the professional and scientific needs of entomologists and individuals in related disciplines.
Hoddle and Stouthamer are among 10 new fellows elected by the Governing Board of the ESA, an honor that acknowledges outstanding contributions to entomology in research, teaching, extension and outreach, administration or the military.
Hoddle, a UC Cooperative Extension specialist and director of UC Riverside's Center for Invasive Species Research, is known for his work on the biological control of invasive arthropods that adversely affect agricultural, urban and wilderness areas.
Stouthamer, a UC Riverside professor of entomology, is known for his research on wolbachia, invasive species and insect-transmitted plant pathogens.
The fellows will be recognized during Entomology 2018, the Joint Annual Meeting of the Entomological Societies of America, Canada and British Columbia, Nov. 11-14, in Vancouver, British Columbia, Canada.
Merenlender elected California Academy of Sciences fellow
In a nominating letter, UC Berkeley biology professor Claire Kremen called Merenlender “an accomplished and impactful conservation biologist.”
Merenlender's work spans an array of topics, from genes to ecosystems and single species management to regional land use planning. Currently she is involved in three main research efforts:
- Land use planning to support biodiversity conservation and climate resilience in California oak woodlands
- Watershed restoration and sustainable watershed management in Mediterranean ecosystems
- Development of effective citizen science and amateur naturalist and steward training programs with lasting benefits for biodiversity conservation
According to the academy, the scientists elected as fellows have shown strong evidence of world-class impact, measured through publications, discoveries and awards. Merelender has published more than 80 papers in conservation biology, including co-writing the book “Corridor Ecology: the science and practice of linking landscapes for biodiversity conservation.” In 2016, Merenlender was recognized for her extension and outreach when she won the UC ANR Distinguished Service Award.
In its selection criteria for fellows, the academy notes that potential candidates are engaged in science communication efforts.
Merenlender is founder and director of the UC California Naturalist program. The program launched in 2012 with five partner institutions and has grown into a network of more than 37 partners. They have collectively offered more than 100 certification courses, training 1,864 naturalists who have contributed more than 100,000 volunteer hours, reaching 53,000 people.
Building on the success of the California Naturalist program, Merenlender is designing a Climate Stewards program to provide outreach, training and engagement with diverse audiences on climate change science and policy. The Climate Stewards advisory team has set the goal of launching the program in 2019.
“As an extension scientist, (Merenlender) is strongly attuned to the importance of conducting research with direct relevance to contemporary environmental challenges and to connecting research with conservation on the ground,” wrote UC Berkeley professor David Ackerly in a letter seconding Merenlender's nomination to be a Fellow of the California Academy of Sciences. – Jeannette Warnert
UC communicators bring home gold, silver and bronze
Six communicators affiliated with UC Davis and UC ANR received a total of 10 awards for excellence from the international Association for Communication Excellence in Agriculture, Natural Resources and Life and Human Sciences (ACE).
They brought home five gold or first-place awards: three silver or second-place awards; and two bronze or third-place awards. “That was quite a haul!” commented an ACE member on Facebook.
Diane Nelson, communication specialist with the UC Davis College of Agricultural and Environmental Sciences, won two golds. One was for promotional writing, “Weighing Pig Personality,” (https://bit.ly/2KDdYmQ), featuring animal science professor Kristina Horback's pioneering research examining the role personality plays in the welfare and sustainable production of pigs. The second gold was for web writing, “The Last Stop: When There's Nowhere Colder to Go,” (https://bit.ly/2M6iOOR), spotlighting research by animal science professor Anne Todgham, who studies how climate change affects polar species. Both of Nelson's submissions drew perfect scores from the judges.
Kathy Keatley Garvey, communication specialist with the UC Davis Department of Entomology and Nematology, won gold for best newswriting, “Why These Youngsters Want to Become Entomologists” (https://bit.ly/2sYwhye), about children of California migratory workers touring the Bohart Museum of Entomology and then staging a press conference to interview director Lynn Kimsey, UC Davis professor of entomology. Judges awarded the news story a perfect score. Garvey also received a silver in the writing-for-the-web category for her Bug Squad blog post, “Once Upon a Monarch” (https://bit.ly/2BrePU5). She writes the blog, launched in 2008, every night, Monday through Friday, on the UC ANR website.
David Slipher, director of marketing and communications for the UC Davis College of Biological Sciences, won gold for best picture story for his piece on “Pigeon Parenting” (https://bit.ly/2KCfCoN), focusing on research from the Rebecca Calisi Rodríguez lab. Calisi Rodríguez is an assistant professor in the Department of Neurobiology, Physiology and Behavior.
Steve Elliot, communication coordinator for the Western Integrated Pest Management (IPM) Center, won two silvers and a bronze: a silver for his photo essay, “America's Arctic Agriculture: Growing Crops, Managing Pests and Monitoring Invasives in Alaska” (https://bit.ly/2OS2Vtc); silver for the diversity awards video category, “Gold Spotted Oak Borer: A Threat to California's Oaks” (https://youtu.be/In2e5atd3ZY); and a bronze for the Western IPM Center's monthly newsletter, “The Western Front” (https://bit.ly/2M5mL6s). The center, a USDA-funded program, aims to promote smart, safe and sustainable pest management to protect the people, environment and economy of the American West, encompassing 17 western states and territories.
Gregory Watry, science writer for the College of Biological Sciences, won a bronze award in the “Writing for Diverse Audiences” (https://bit.ly/2M4Nq3o) in a diversity awards category. The story described undergraduate research opportunities in Calisi Rodriguez's lab.
ACE is a worldwide association of communicators, educators and information technologists, offers professional development and networking for individuals who extend knowledge about agriculture, natural resources, and life and human sciences. The awards were presented Aug. 7 at the 2018 Ag Media Summit held in Scottsdale, Ariz., where ACE members joined forces with U.S. crop and livestock news media professionals. – Kathy Keatley Garvey
Maggie Reiter joined ANR on May 9 as an area environmental horticulture advisor in Fresno, Madera, Tulare and Kings counties.
Prior to joining UCCE, Reiter was a graduate research assistant at the University of Minnesota from 2013 to 2016. She participated in research projects aimed at increasing winter hardiness in cool-season grasses, identifying salt-tolerant roadside grasses, improving turfgrass seed production, evaluating varieties in the National Turfgrass Evaluation Program trials, and communicating information through the extension program. Reiter also worked on the agronomy staff of several golf courses from 2008 to 2015.
Reiter earned a B.S. in horticulture and an M.S. in applied plant science, both from the University of Minnesota.
Reiter is based in Fresno and can be reached at (559) 241-7504 and email@example.com.
In the 60 years that the University of California has operated its beautiful 5,358-acre Research and Extension Center in Hopland only a handful of people have helped to manage the site as superintendent. Dave Koball, former vineyard manager at Fetzer Bonterra, is following in the footsteps of Bob Keiffer in this role.
Before joining ANR, Koball had worked for Fetzer since 2000, most recently as director of research and education. From 1994 to 2000, he was vineyard manager for Kohn Vineyards.
Koball earned his M.S. in plant pathology at Cornell University and B.S. in plant pathology at UC Davis. He returned to UC Davis as a postgraduate researcher in John Mircetich's lab, studying strawberry root rot in 1993 and 1994.
“The job of superintendent at the Hopland REC has always been something of a balancing act – mixing the needs of many and various research projects on the site with the desire to practice sustainable land management,” said Kim Rodrigues, Hopland REC director. “Dave's established working relationships with our community partners will advance our research and outreach efforts and strengthen our current team efforts.”
“I am really looking forward to entering the California Naturalist program that is run from the center, as well as participating in many of the public events held there, from sheep shearing to the monthly hikes,” Koball said.
Koball can be reached at firstname.lastname@example.org and (707) 744-1424 Ext. 112.
Andy Lyons joined ANR on March 14 as coordinator for the Informatics and GIS statewide program (IGIS).
From 2006 to 2009, Lyons was a monitoring and evaluation specialist for the UN Food and Agriculture Organization office in Johannesburg, where he spearheaded the development of a monitoring and evaluation framework for a regional food security program and developed monitoring protocols for projects promoting low-input farming, input trade fairs, gardens, small-scale irrigation, animal health and nutrition education. In the early 2000s, he worked as a conservation planner for the Wildlife Conservation Society in Zambia, and as a program evaluator for CARE International. Lyons served as a U.S. Peace Corps volunteer from 1991 to 1994 in The Gambia, West Africa, where he taught high school math and physics, and developed databases for the Ministry of Education.
Lyons has a Ph.D. in environmental science policy and management from UC Berkeley. He also has a M.S. in wildlife ecology and conservation from the University of Florida, and a B.A. in mathematics from Duke.
Lyons is based at 130 Mulford Hall #3114 at UC Berkeley and can be reached at email@example.com.
Akif Eskalen, UC Cooperative Extension specialist in the Department of Plant Pathology at UC Riverside, and John Kabashima, UCCE advisor emeritus, received the Award of Arboricultural Research from the Western Chapter International Society of Arboriculture.
The award recognizes their research on the polyphagous shot hole borer, a beetle that is causing severe fusarium dieback damage to avocado and landscape trees in Southern California. The beetle has a symbiotic relationship with fungi. When the beetle burrows deep inside the tree, it transmits the fungi, which cripples the tree's water-transporting mechanism and blocks the transport of water and nutrients from the roots to the rest of the tree.
They received the award at the 2016 Western Chapter ISA Conference in Anaheim on May 3, 2016.
California Rangeland Trust presented its 2016 Conservation Impact Award to Ken Tate, UCCE specialist and professor in the Department of Plant Sciences at UC Davis.
With 102 peer-reviewed publications, Tate leads cutting-edge research in the fields of rangeland ecology and agro-ecosystems, providing tools for effective rangeland management decisions. Tate's career at UC Davis spans 21 years where he held positions such as vice chair for outreach and extension in the Department of Plant Sciences.
“As the go-to guy for all things range science, Tate's research, outreach and education has had a significant impact on rangelands throughout California, the United States and the world,” California Rangeland Trust wrote in its news release.
Tate, the Russell L. Rustici Endowed Chair of Rangeland Watershed Science, received the award at a special farm-to-fork gala on May 21.
Doug Parker has been named president of the Universities Council on Water Resources (UCOWR), the association of universities and organizations leading in education, research, and public service in water resources.
Parker, who is director of the UC ANR's California Institute for Water Resources, will serve as president for one year, then a year as past-president.
UCOWR members and delegates are at the forefront of water resources-related research and education, and represent various fields of natural and social science. Each member university appoints up to eight faculty or staff as UCOWR delegates. Others may join as individual members.
UCOWR's main objectives are to:
- Facilitate water-related education at all levels
- Promote meaningful research and technology transfer on contemporary and emerging water resources issues
- Compile and disseminate information on water problems and solutions
- Inform the public about water issues with the objective of promoting informed decisions at all levels of society
To achieve these goals, member institutions engage in education, research, public service, international activities and information support for policy development related to water resources. UCOWR holds an annual conference that provides a forum to explore key and timely topics of interest to water resources researchers and educators. UCOWR also publishes the Journal of Contemporary Water Research and Education, presenting both scholarly work and current water resources news.
Five communicators associated with ANR received awards from the Association for Communication Excellence in Agriculture, Natural Resources, and Life and Human Sciences on June 15 at its annual conference in Memphis, Tenn.
The UC Statewide Integrated Pest Management Program's "Pest Wheel Set" earned a bronze award for Cheryl Wilen, area IPM advisor and IPM advisor extension coordinator, and Scott Parker, UCCE community educator in San Diego. The set includes two interactive wheels, in English on one side and Spanish on the other.
The Pest Wheel helps the user identify and manage 12 common pests, including ants, snails, powdery mildew and scale insects. IPM also offers the Weed Wheel, which covers 12 common garden and landscape weeds, including crabgrass and yellow nutsedge.” (The Pest and Weed Identifier Wheels can be purchased for $4 each. To order, contact Scott Parker at firstname.lastname@example.org or (858) 822-6932.)
Diane Nelson, a senior writer with the College of Agricultural and Environmental Sciences, won a gold award in promotional writing from ACE for her news release on groundwater banking, “Farmland May Provide Key to Replenishing Groundwater.” The article discusses the research of CA&ES faculty members Helen Dahlke, Ken Shackel and Astrid Volder and UCCE specialist Toby O'Geen.
Kathy Keatley Garvey, communications specialist with the UC Davis Department of Entomology and Nematology, won a gold award for her photograph of two youths getting acquainted with a rose-haired tarantula. Garvey also won silver awards for her feature story on entomologist Jeff Smith of the Bohart Museum of Entomology and for her photo series “Miracle of Life.” A photo of two praying mantids mating earned her a bronze award.
ACE, an international association of communicators, educators and information technologists, offers professional development and networking for individuals who extend knowledge about agriculture, natural resources, and life and human sciences.
To see all of the award-winning photos, see the Bug Squad story at http://ucanr.edu/blogs/blogcore/postdetail.cfm?postnum=20760.