California’s forests and urban canopies are under increasing pressure from invasive pests, and staying ahead requires knowledge, strategy, and action. This in-depth seminar brings together leading experts to break down the real-world impacts of today’s most damaging invasive insects, including ISHB, GSOB, SAPW, and DPLB.
Attendees will gain practical insights into identification, current research, and proven management approaches, capped off with an outdoor demo showcasing tools and techniques you can apply immediately.
Date: Wednesday, April 1st 2026
Time: 9:00 AM - 1:30 PM
Location: Tilden Regional Park in the Berkeley Hills
Wildcat Canyon Road at Shasta Road, Berkeley CA 94708
Room Name: Brazilian Room
Free Event
4 ISA CEUs approved
Lunch is provided
Parking instructions will be provided once registered.
Registration
Registration closed due to capacity.
Agenda
9:00–9:30 AM Registration / Sign-In / Breakfast
9:30–9:35 AM Introduction
Joe Lockyer, North California Territory Manager, Rainbow Ecoscience
- Welcome
- Safety brief
- Housekeeping logistics
- Review the agenda for the day and expectations
- Introduction of guest speakers and Rainbow staff
9:35–10:00 AM Impacts of Invasive Pests
Imagine Shaw, Technical Advisor, Rainbow Ecoscience
Invasive insects and pathogens are reshaping our landscapes faster than trees can adapt. Emerald ash borer, Dutch elm disease, chestnut blight, boxwood blight, invasive shot hole borers, goldspotted oak borer, South American palm weevil, and emerging vascular diseases demonstrate how rapidly invasives overwhelm hosts.
This session explores plant defense systems through a genetic and evolutionary lens, examining why traditional IPM tools such as identification, quarantine, and exclusion can slow, but not stop, these threats. While all management strategies carry impacts, chemical protectants remain critical for preserving trees during active infestations. Without intervention, widespread tree loss is not a risk, it is inevitable.
Imagine Shaw
H. Imagine Shaw is an experienced arborist and horticulturist. ISA certified, she has a background in consulting, plant healthcare, and sustainable landscape management. Shaw is passionate about educating communities and resides on the board of both the Southern Chapter of the ISA-Tennessee State Director/Education Committee and the Tennessee Urban Forestry Council Liaison/Education Committee.
10:00–10:45 AM Managing Mediterranean Oak Borer
Dr. Michael Jones, Forestry Advisor, University of California Cooperative Extension and Dr. Curtis Ewing, Cal Fire; Forest Entomology & Pathology Specialist
We will give an overview of the Mediterranean oak borer infestation in California and what we currently know about its biology, ecology, and best management practices.
Dr. Michael Jones
Dr. Michael Jones is the University of California Cooperative Extension Forestry Advisor for Mendocino, Lake, and Sonoma Counties. He specializes in forest health and disturbance ecology. He conducts and extension program the focuses on keeping coastal conifer forests and oak woodlands healthy by encouraging good stewardship through outreach, education, and research.
Dr. Curtis Ewing
Dr. Curtis Ewing is an Environmental Scientist with the California Department of Forestry & Fire Protection. He specializes in timberland, urban forest, and natural landscape health in California. He consults with all state and private landowners to assess and manage tree health.
10:45–11:30 AM Managing Shothole borer and Greater Shothole Borer
Gabe Verduzco, Arborologist, Rainbow Ecoscience and Dr. Brian Woodward, Regional Forest Advisor for the Santa Cruz Mountains, University of CA Cooperative Extension
The greater shot hole borer (Euwallacea interjectus) was confirmed in Santa Cruz County in 2024 and represents a new invasive ambrosia beetle–fungus complex in California. It differs from previously established shot hole borers in being larger, producing larger entry holes, and carrying a different fungal symbiont (Fusarium floridanum).
Current detections are centered in Santa Cruz County, primarily in riparian and urban hosts. Key unknowns include host range, rate of spread, and mortality risk under California conditions. Ongoing work of our partners focuses on delimitation of infestation, host susceptibility, and early response strategy development.
Dr. Brian Woodward
Brian Woodward, PhD is the Regional Forest Advisor for the Santa Cruz Mountains (Santa Cruz, Santa Clara, and San Mateo Counties). He leads a forest management and ecology research and extension program addressing the challenges facing landowners, industry, non-profits, and government forest property owners in the Santa Cruz Mountains.
11:30 AM–12:15 PM Lunch
12:15–1:00 PM Best Management Practices for Plant Health Care Applications
Dr. Drew Zwart, Plant Pathologist and Physiologist – Bartlett Tree Research Laboratories (West)
Effective plant healthcare relies on delivering treatments in ways that maximize efficacy while minimizing environmental impact and stress to trees. This presentation will review best management practices (BMPs) for applying plant healthcare products, including soil-applied and systemic options, with a primary focus on modern tree injection techniques. Attendees will gain insights into selecting appropriate delivery methods, understanding how tree physiology influences uptake, and implementing injection protocols that support tree vitality while ensuring predictable, consistent results.
Dr. Drew Zwart
Dr. Drew Zwart is a plant pathologist and physiologist and has been on staff at the Bartlett Tree Research Laboratories for 20 years. He conducts research and provides training and scientific support throughout Bartlett’s western operations, including California, Arizona, Oregon, and Washington. Drew conducts research on plant pathology and stress physiology, with a focus on sustainable practices and climate resilience. Dr. Zwart earned his PhD at the University of Washington – Center for Urban Horticulture, studying the interaction of plant stress and disease susceptibility. Dr. Zwart also holds an B.S. in Plant and Soil Science from Cornell University and an M.S. in Plant Pathology from Clemson University. Drew is an ISA-certified arborist and a Registered Consulting Arborist.
1:00–1:05 PM Afternoon Break & Assemble Outside
1:05–1:35 PM Tree Injection Demonstrations & Training
Gabe Verduzco, Arborologist, Rainbow Ecoscience
During this field demonstration, participants will learn about tree injection tools used to deliver effective treatments. We will cover proper application techniques and review in-field best practices to ensure safe, accurate, and successful tree injections.
Gabe Verduzco
Gabe brings 18 years of experience in the plant healthcare field, including USDA research, horticulturalist for a botanical garden, starting a small fruit farm while living in Hawaii, and a research associate with the University of California, Agriculture and Natural Resources Division. He is excited to bring his expertise in PHC with invasive tree pests and plant diseases in his region. Gabriel holds his ISA Certified Arborist license as well as his California PCA license – Pest Control Advisor.
1:35 PM Closing Remarks
