Multi-Day In-Person Workshop
Tree Biology
Oct. 6-8, 2026 | Sparta, Wis.
This three-day Tree Biology Workshop combines classroom learning with hands-on field experiences to help participants better understand how trees grow and respond to their environment. Through interactive discussions, live dissections, and real-world case studies, attendees will explore tree anatomy, wood structure, root systems, and the science of Compartmentalization of Decay in Trees (CODIT). Participants will also learn how to evaluate tree structure and compare different nursery stock and planting systems. Whether you are an arborist, urban forester, landscape professional, or passionate tree enthusiast, this workshop will provide practical, science-based knowledge that can be applied to improve tree health, planting success, and long-term tree care.
WORKSHOP DETAILS
Workshop Fee: $1,000
RSVP Now!Space is limited to the first 20 participants. RSVP with number of attendees early to secure your spot. Registration closes September 25, 2026 or when full.
Mail checks to Zillmer Tree Management, N290 Pine Place, Merrillan, WI 54754.
The workshop itself will take place at Legacy-Trees® research and development facility, located at 3970 Benton Rd., Sparta, WI 54656.
The Tree Biology Workshop Agenda may be subject to change.
The workshop will be held at Legacy-Trees® research and development facility, located at 3970 Benton Rd., Sparta, WI 54656.
This workshop is a combination of classroom instruction and outdoor fieldwork. Both will emphasize hands-on experiences intended to enhance your understanding of how trees grow and respond to their environment and the forces that act upon them.
All instructional support materials will be provided.
Be prepared to get dirty. Bring outerwear appropriate for unpredictable October weather. In addition, bring the following:
- Hard Hat
- Hearing Protection
- Eye Protection
- Sturdy Footwear
- Work gloves
We are seeking pre-approval for ISA CEUs.
This workshop is designed for arborists, urban foresters, municipal forestry staff, landscape professionals, nursery growers, consulting arborists, tree care company owners and employees, parks and grounds managers, extension educators, and other green industry professionals who want to deepen their understanding of tree biology and improve their tree planting and establishment practices. Whether you are responsible for planting, maintaining, or managing trees, this course provides science-based knowledge and practical techniques that can be immediately applied in the field to improve tree health, longevity, and performance.
Participants are responsible for booking their own accommodations. A few hotel options are listed below for your convenience, though this is not a comprehensive list.
Hotels in Black River Falls
Hotels in Sparta
Workshop Instructors
Les Werner, Ph.D.
Professor Emeritus of Forestry and Founding Director of the Wisconsin Forestry Center, University of Wisconsin-Stevens Point
Les Werner, Ph.D., is a professor emeritus of forestry and the founding director of the Wisconsin Forestry Center at the University of Wisconsin-Stevens Point, specializing in the intersection of tree biology, soil science, and urban forest management. With over four decades of experience bridging academic research and fieldwork, Dr. Werner’s work primarily focuses on nutrient demands, root system development, soil microbiology, tree defects and injury physiology. A co-author of the ISA Best Management Practices: Tree and Shrub Fertilization, his biological research provides arborists with critical, science-based insights into maintaining long-term tree health and structural integrity.
Ronald Zillmer
Founder and President of Legacy-Trees®
Ron Zillmer is the Founder and President of Legacy-Trees® and an internationally recognized expert in tree biology and root physiology. With more than 30 years in the tree care industry, he developed the Legacy-Trees® planting method, a science-based approach to improving tree establishment and long-term health. Ron holds degrees in Urban Forestry from the University of Wisconsin–Stevens Point and Tree Physiology from Purdue University and has served in leadership roles with the Wisconsin Arborist Association and the International Society of Arboriculture. His engaging workshops combine research, real-world experience, and hands-on demonstrations to give participants practical techniques for successfully establishing healthy, resilient trees.
workshop partner
