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Volume 03: A Guide for Addressing Collisions with Trees in Hazardous Locations

Trees Are the Most Commonly Struck Fixed Object


One of the most common causes of fatal and severe injury crashes, on rural roads in particular, is a vehicle leaving the road and striking a fixed object. In fatal crashes involving a fixed object, trees are the objects most often struck.


Eight percent of fatal crashes—more than 3,000 a year—involve crashes into trees. More than half of these crashes occur under dark conditions, half occur on curved roads, and half involve alcohol.

A Guide for Addressing Collisions with Trees in Hazardous Locations focuses on measures to reduce the harm in tree crashes after encroachment on the roadside has occurred.



  • Prevent trees from growing in hazardous locations.
  • Eliminate the hazard and/or reduce the severity of the crash.

Download this guide: http://gulliver.trb.org/publications/nchrp/nchrp_rpt_500v3.pdf

NCHRP 500-3
Trees in Hazardous Locations

Trees are the objects most commonly struck in Run-Off-Road (ROR) collisions, and tree impacts are generally quite severe. This guide focuses on measures directed at reducing the harm in tree crashes.

Download the guide in PDF

View the Guide and Appendices in HTML

Order a printed copy

Related publications


Collisions With Trees One-Pager


Self Assessment Tool


Integrated Safety Management Process