Washington State Issues Tree Trimming Hazard Alert Following Spike in Worker Fatalities
A new alert from Washington State’s Department of Labor & Industries urges employers to strengthen fall protection, supervision, and rigging practices after multiple fatal tree trimming incidents.
- By Stasia DeMarco
- Oct 13, 2025
Washington State safety officials are warning employers and workers in the tree care and landscaping industry to strengthen fall protection and rigging practices following a recent increase in worker deaths. A new hazard alert issued by the Washington State Department of Labor & Industries (L&I) reports that eleven landscaping workers in the state died between 2020 and 2024, most while performing tree trimming tasks. Nationwide, 228 landscaping workers were killed in 2023, according to the U.S. Bureau of Labor Statistics, underscoring the high-risk nature of the industry.
The Tree Trimmer Hazard Alert outlines several fatal incidents and identifies recurring safety failures that contributed to the deaths. Among them were climbers who accidentally cut their lifelines, workers struck by falling branches, and rigging failures during lowering operations. In one case, a worker climbing a 120-foot Douglas fir inadvertently severed his flip line while cutting limbs and fell to the ground. In another, a trimmer was fatally struck by a suspended branch that broke unexpectedly. A third incident involved a shock load when a crew wrapped a lowering rope directly around a tree instead of using proper rigging equipment, causing the rope to whip upward and pull the climber from the trunk.
According to the alert, these tragedies highlight the need for pre-job hazard assessments, qualified supervision, and the exclusive use of arborist-grade ropes, harnesses, and rigging systems. L&I recommends that all tree work be overseen by a Certified Treecare Safety Professional (CTSP) or ISA Certified Arborist who can evaluate jobsite hazards and ensure compliance with ANSI Z133-2017 safety standards. Workers should receive training on safe climbing techniques, emergency descent procedures, communication protocols, and rescue planning. Employers are also encouraged to conduct post-incident reviews to identify root causes and improve safety practices.
State safety officials stress that proper planning and equipment selection can prevent future fatalities. Even experienced climbers, they note, can make critical errors under pressure if protocols are not followed or equipment is improperly used. The hazard alert urges companies to treat tree trimming as a highly technical operation requiring formal safety management and supervision, not as routine groundskeeping work.
Tree trimming remains one of the most dangerous jobs in the United States, combining fall hazards, struck-by risks, and electrical exposure. L&I’s latest alert serves as a reminder that comprehensive safety planning—supported by qualified leadership and continuous training—is the most effective defense against deadly incidents in the field.
For more information, view the full alert here: Preventing Tree Trimmer Deaths (PDF)
About the Author
Stasia DeMarco is the Content Editor for OH&S.