Trees and Litigation: Considerations for Defendant and Plaintiff Cases

TASA ID: 3447

Based on my experience working with plaintiff and defendant cases, this article focuses on trees in the urban landscape and provides information that may prove useful for attorneys to consider in tree-related cases.

As with any plant or animal, age and time cause physical and mechanical breakdown in the organism.  Since trees are typically large, heavy organisms, physical or structural failure can have catastrophic results. Because trees are planted in close proximity to property and the general public, accidents resulting in lawsuits are inevitable. Therefore, it is incumbent upon the defendant or plaintiff attorney to fully understand and consider the many dynamics involved with tree-related accidents.

If a client or attorney is considering a lawsuit involving a tree-related accident, the following information may assist in discovery and research for defendant or plaintiff cases.


If a tree failure occurred in or on public property, including streets, parkways, medians, right of ways, slopes, parks, recreational and governmental facilities, most likely a landscape architect provided the landscape and irrigation design, details, and specifications for the public improvement.  The same is true for most commercial and industrial properties, multi-family housing, and master planned communities.

One of the many roles of the Landscape Architect is to consider the form and functionality when creating a landscape design for a given project.  Landscape plant palettes for public improvements should include "safe" trees for use in and around public improvements. Functionality, including public safety and maintenance considerations, should take precedence over form or aesthetic consideration. Therefore, when researching a case, examine the landscape plant palette and overall design from a functionality and safety perspective.

Typical functional considerations for trees may include:

  • View or sight line corridors.
  • Screening
  • Pedestrian egress and access
  • Visual accent, monumentation
  • Historical value
  • Shading, cooling
  • Soil stabilization
  • Erosion control
  • Privacy
  • Community or neighborhood theme

While examining functionality, consider whether it was compromised or inhibited by incorrect plant or tree selection or other aesthetic.  Perhaps the original design concept envisioned a small or medium-sized tree planted twenty feet from the nearest sidewalk, but in reality a 100' tall Eucalyptus is five feet from the sidewalk. 

Sometimes, tree failure and resultant damages are fairly obvious, and with proper forensic analysis, a certified arborist can often times identify the cause of the failure. However, many times a tree may be involved in a case without any failure involved. An out of control vehicle veers off the highway and crashes into a tree in a parkway or median strip. Who is at fault?  Did the tree cause the accident or resultant damages?


This real estate maxim should be applied to tree location in the landscape. Tree location and tree type are primary issues in tree accidents.  Whenever trees are planted in close proximity to people and property, accidents will occur.  Trees located within public right of ways, medians, parkways, parks and recreation facilities create a much higher level of risk and pose an increased hazard to property and the general public.


Street trees are commonly planted throughout urbanized streets in medians, parkways, left hand turn pockets, sidewalk planters, and other confined spaces. Far too often, trees are crammed into small, confined spaces that are inadequate for proper root growth and mechanical support.          Small trees left unmaintained in traffic planter areas quickly become large trees that can block or impair traffic sight lines and distances, drop limbs and leaf litter on traffic, and create hazardous conditions for the general public. 

Tree location is vital in analyzing traffic accidents.  Investigations should focus on size and location of the tree, lowest permanent branch, canopy size and density, and how the physical qualities of the tree and location of the tree impact the accident site. Also, consider if the tree was isolated or located in a grove or mass planting of trees.  The outer trees in groupings or groves typically absorb more environmental stresses and protect the inner trees. If the outer trees have been pruned or removed, the inner trees may be structurally compromised.

III.         TREE TYPE 

Perhaps the most difficult aspect in design is tree selection.  As previously mentioned, design professionals select plant material based on the functionality and form (aesthetics). Therefore, the "ideal" tree for a given location takes into consideration the site location and site-specific conditions, the functional use and requirements, combined with thematic and aesthetic considerations, to determine plant selection.  If one or more of these considerations is ignored, an incorrect tree selection can result.  Incorrect tree selection abounds. Driving down urban streets, you can view inappropriate street trees such as Eucalyptus or Ficus in confined parkways or planters, tree root crown or flairs growing over curbs and cracking sidewalks, trees topped or sheared as limbs extend into traffic lanes.

The type of tree involved in an accident may be as important as the tree location. Proper tree identification should include the genus, species and particular variety or cultivar, as well as common name. Research the tree cultural requirements, growth and maintenance characteristics.  Understanding the particular growth habits and characteristics of the tree may strengthen your case.

Site investigation may very well yield evidence pertaining to possible design flaws, poor location and incorrect tree selection.  Certain trees are known to be dangerous, Eucalyptus trees are known as "widow makers" for their habit of dropping large scaffold limbs or suffering complete structural failure without any notice or warning.



Coral trees (Erythrina caffra) grow very fast, with enormous, heavy soft wooded limbs that can shatter in storms or drop unexpectedly.  Even with these obvious defects, these two tree genera have been heavily planted in the 1970-1990's, with agencies, property managers and owners having to deal with the resultant increased risk and liability inherent in these older, dangerous trees. 


Over time, the landscape and nursery industry has introduced thousands of improved tree hybrids and varieties. Newer plant materials are developed for improved specific characteristics including flower, fruit, growth rate, size, drought tolerance, insect and disease resistance and decreased maintenance requirements.  As older, dangerous trees are removed, newer, safer and improved tree varieties are being utilized.

Unfortunately, the urban landscape includes countless thousands of older, neglected and poorly maintained trees, and municipalities have shrinking budgets and higher priorities for asset allocation.  Deferred tree maintenance results in increased risk of tree failure and increased liability for property owners, public agencies and property managers. It only takes one storm or wind event to bring down heavy, overgrown tree limbs or entire trees. Existing dead wood, damaged or dangling branches eventually will fall from trees with dangerous results. Old palm fronds can become unmanned, guided missiles in windstorms.

Public agencies, property owners and managers are responsible for trees on their property. It is their responsibility to maintain their tree resources and provide for public safety. Premises liability cases involving tree accidents are increasing, and a tree failure can no longer be defended as an "act of God."  With proper annual inspection and follow up maintenance, a tree failure may be averted. 

When investigating a tree accident, discover whether the property owner, manager or agency has a documented tree risk policy.  Managing risk through a documented policy is essential. It clearly defines management's attitude and actions they will take to manage risk associated with their tree resources. When implemented, the policy forms the basis for a defense in the event of a tree failure and any resultant litigation.  Establishing and maintaining an active tree risk and management policy indicates ownership or management's commitment toward improving and maintaining public safety. In the event of a lawsuit, having a tree risk policy plan is certainly preferable to having no policy at all.

Consider past maintenance records, including tree logs, inventories, past recommendations or service visits.  Is there any kind of maintenance record, or was the tree(s) ignored and never maintained?

Was the tree hazard identified prior to the failure?  If on public land, was the tree hazard called into the municipal agency responsible for tree inspections and maintenance? If so, how and when did the agency respond?  Does the agency responsible for tree care and maintenance have a documented tree risk policy? If not, how do they prioritize and manage the risk associated with older trees on public property? Does the agency rely on the general public to call in a potential tree hazard, or do they take pro-active action to inspect older, suspect trees in higher use areas on their own?  Unfortunately, many municipalities rely on public- generated information, a very dangerous reactive rather than pro-active management practice. The public is not educated in arboriculture or tree care and should not be relied on as an inspection tool for a municipality.

In summary, trees planted in the urban landscape in close proximity to pedestrians, motorists, the general public, and property carry inherent risk.  As they age, the risk of accident increases over time. Design, tree selection, location and maintenance can play a positive or negative role over time in minimizing or increasing tree risk.  By using a variety of landscape professionals, including a certified arborist, tree risk can be minimized, and functionality and aesthetics maximized.

Article Acknowledgements:

Mr. Mark Duntemann, Natural Path Urban Forestry, Seminar on Tree Risk Management, August 20, 2010.

This article discusses issues of general interest and does not give any specific legal or business advice pertaining to any specific circumstances.  Before acting upon any of its information, you should obtain appropriate advice from a lawyer or other qualified professional.

This article may not be duplicated, altered, distributed, saved, incorporated into another document or website, or otherwise modified without the permission of TASA.

Previous Article Human Injury from a Food Product
Next Article Changes in PA Workers' Compensation Act 2014
Tasa ID3447

Theme picker


  • Let Us Find Your Expert

  • Note: This form is to be completed by legal and insurance professionals ONLY. If you are a party in a case that requires an expert witness, please have your attorney contact TASA at 800-523-2319.

Search Experts

TASA provides a variety of quality, independent experts who meet your case criteria. Search our extensive list of experts now.

Search Experts