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LinkedInPosts Tagged: Irvine
REC System Director Haver encourages systemic approach to agriculture
Agriculture generates $59 billion and employs nearly 400,000 individuals in California. The industry, however, is often threatened by challenges like climate change, land conversion and water scarcity. Motivated to act, Sustain Southern California – an organization associated with UC Irvine Beall Applied Innovation – hosted a roundtable discussion on Feb. 20 featuring subject matter experts including Darren Haver, director of UC Agriculture and Natural Resources' Research and Extension Center System.
During his keynote address, Jose Arriaga, Orange County Agricultural Commissioner, defined sustainability as food and fiber production that does not compromise the ability for future generations to meet their needs. In doing so, he acknowledged the benefit of discussing such timely topics with key players, especially for places where agriculture is not as prevalent as it used to be.
“Many people don't think of Orange County as a place for agriculture. It's probably because less land is being reserved for agriculture, not like back in the day. And that worries me,” said Arriaga.
The first roundtable discussion centered on sustainable agriculture, with Haver participating alongside other industry leaders based in Southern California, including A.G. Kawamura of Orange County Produce, Steve Brazeel of Sunterra Produce and Elevated Foods, Anthony Curci of Buttonwood Ranch and Parker Cohn from Performance Resource Management.
In discussing today's generation, Haver said that he has seen a shift over the last few decades away from yield alone, which used to be the most important aspect of production in agriculture. Today, much more attention is dedicated to sustainability – a change that Haver attributes to the younger generation of researchers and plant scientists working in agriculture.
There has also been an emphasis on sustaining the environment while maintaining economic progress. Haver recognized these important elements, but highlighted the social impact of sustainability, too.
“I don't have all the answers, but I do believe that addressing the environmental, economic and social aspects of agriculture is important. I also think that these factors should be addressed systemically rather than in silos,” said Haver.
Southern California agricultural producers, in particular, are responsible for $7.8 billion in gross receipts and nearly 100,000 jobs directly related to agriculture. In Orange County alone, where Haver is based at the South Coast Research and Extension Center, agriculture makes up $86 million of total economic output, with nurseries leading as a top commodity followed by fruit trees, vegetable production and livestock and apiary.
Katie Thompson-Peer: Fruit Flies as a Model to Study Dendrite Regeneration
The fruit fly, Drosophila melanogaster, is widely used for biological...
This is the fruit fly, Drosophila melanogaster, that Katie Thompson-Peer uses in her biological research. (Photo by André Karwath, Wikipedia)
After shothole borer invasion, UC Irvine becomes ‘perfect testing ground’
Results help inform best practices for managing the disease-causing beetle
The University of California, Irvine campus is home to a vast urban forest consisting of approximately 30,000 trees located in a mix of landscape, riparian and open space settings. In the mid-2010s, that forest came under threat from an invasive species of beetle that arborists and pest researchers were just learning about – the polyphagous shothole borer.
The tiny beetles, which may have arrived in California from their native Southeast Asia via infested shipping materials, tunnel into trees and introduce a fungus that serves as food for adult beetles and their larva.
As the fungus grows, it colonizes the tree's vascular system, blocking transport of water and nutrients. This causes a disease called Fusarium dieback that can kill branches or entire trees.
One reason the beetles were such a threat at UCI was the high number of sycamores on campus, especially in Aldrich Park at the campus center. Hundreds of cottonwoods, native willows, golden rain and coral trees also were affected. In total, the beetles attacked more than 2,000 trees, including 75 different tree species.
A variety of approaches to controlling beetle
To better understand and tackle this problem, UCI's Facilities Management department and Office of Environmental Planning and Sustainability collaborated with researchers affiliated with UC Agriculture and Natural Resources and UC Cooperative Extension. In addition, pesticide-manufacturing companies, pest control advisers and arborists provided materials and labor to help offset the cost of research.
“UCI was the perfect testing ground to determine integrated pest management strategies for this beetle/disease complex,” said John Kabashima, UCCE environmental horticulture advisor emeritus. “Our research was multifaceted, delving into early detection, monitoring and sampling, and cultural and chemical management.”
Kabashima said UCI provided the researchers with “a lot of freedom” to try a variety of approaches and study the results over time.
“We could cut down and sample trees or leave selected infested trees alone; we explored a variety of pesticide/fungicide combinations and application techniques,” he said. “That freedom resulted in many of the management solutions that are used today to effectively control this pest.”
UCI and the researchers also established a full inventory of affected trees on campus, evaluating severity of infestation by the number of entry/exit holes and signs of dieback. One important key to management is getting rid of “amplifiers” – heavily infested trees that are both hazardous and a source of beetles to spread to other trees.
“Typically, shothole borer infestations begin with just a few trees that for some reason are highly attractive to the beetles – perhaps based on tree species, tree spacing, irrigation conditions or other factors,” Kabashima said. “Over time, the beetles and fungus multiply largely undetected in those few trees. When the beetle population reaches a critical point and the trees begin to die, the female beetles fly to adjacent trees in a secondary invasion, eventually infesting many trees over a large area.”
An opportunity to diversify UCI's urban forest
At UCI, that initial invasion took place in landscaped areas containing many large, majestic sycamores that were planted when the campus began operations in the mid-1960s.
Over several years, UCI removed 700 heavily infested trees, including many of those historic sycamores, and replaced them with other tree species.
Today, the forest at UCI is very different than it was in 2015. While shothole borers have not been eliminated completely, their presence is reduced significantly, and UCI now has the tools to manage them effectively. Reforestation efforts resulted in a diverse treescape that is not only more sustainable but also beautiful.
“Managing a 1,500-acre campus with 30,000 trees is a never-ending process,” said Richard Demerjian, UCI's assistant vice chancellor, Campus Physical & Environmental Planning. “Our forest continues to evolve, with an ongoing focus on increasing diversity and plant health.”
Demerjian also noted that UCI is now starting to consider planting new sycamore trees on a limited basis.
A primer on effective shothole borer management
Whether managing a forest of thousands of trees or just a few trees, landscape managers and residents can apply many of the lessons learned at UCI to control invasive shothole borers and other tree pests.
- Avoid monocultures. Tree diversity provides beauty and resiliency.
- Keep trees healthy. Proper irrigation and maintenance will keep trees strong and help protect them from shothole borers and other pests.
- Check trees. Look for the common signs and symptoms of infestation such as beetle entry/exit holes. Regular monitoring ensures that infestations are managed early, before they cause dieback or tree death.
- Confirm suspected infestations. Use the detection tool at www.ishb.org.
- Review management options. For trees with low infestation, prune the infested branches and monitor the tree's health over time. In non-riparian, urban settings, consider treating low and moderately infested trees with pesticides/fungicides demonstrated to be effective against the pest-disease complex (A licensed professional will be needed to apply the treatments). Severely infested trees may require removal.
- Call in a professional. A certified arborist or pest control professional would be able to provide recommendations based on the tree's condition. The local county Agricultural Commissioner's Office and UC Cooperative Extension office may have additional knowledge about current shothole borer monitoring and management programs in your area.
- Take care of green waste. The beetles can survive in cut wood for weeks or even months. Proper disposal of green waste includes chipping infested wood, followed by solarizing or composting the chips.
- Replant wisely. Begin planting new trees only after removing all amplifiers and establishing an ongoing monitoring program. Consider the current concentration of tree species when deciding what type of trees to plant.
Tobin Hammer and Bees: Probing the Mystery of the Missing Microbes
Don't miss this seminar by Tobin Hammer Wednesday, April 13 on "Mystery of the...
A yellow-faced bumble bee, Bombus vosnesenskii, foraging on buckwheat along California coast. (Photo courtesy of Tobin Hammer)
