Live Webinar 4/23/26 – Phosphonates, The Lure of The Silver Bullet

Presenter: Chelsi Abbott

Format: Live Webinar

Date: 4/23/26

Time: 12:00PM-1:00PM EST (Please adjust for your time zone)

CEUs:

ISA BCMA Science : 1

Climber Specialist: 1

ISA Certified Arborist: 1

Utility Specialist: 1

Urban Forester Specialist: 1

Aerial Lift Specialist: 1

Objectives:

1. Objectives:
2. Define phosphonates and distinguish them from other plant health care
   products.
3. Explain the proposed modes of action of phosphonates within woody plants.
4. Summarize current research findings on the use of phosphonates for general
   tree decline and disease management.
5. Identify limitations, uncertainties, and gray areas associated with
   phosphonate use.
6. Apply an evidence-based framework to determine when phosphonates are, or
   are not, an appropriate management tool.

Course Description:

Phosphonates are often promoted as a cure-all for tree decline and disease, but what does the science actually support? This webinar explores what phosphonates are, how they function within the plant, and their proposed modes of action. We will review current research on their effectiveness in managing general decline and specific diseases, while also addressing limitations, misconceptions, and the gray areas that still exist. This talk is designed to help arborists and urban foresters make informed, evidence-based decisions rather than relying on the promise of a “silver bullet.”