Aspen boasts a number of outstanding natural resources including having the premier high-altitude community forest in Colorado. The City of Aspen has established a dynamic natural resource program that encompasses both the urban forest and the surrounding natural resources, earning it the distinct designation of being a Tree City USA, as well as being accredited by the Society of Municipal Arborists. This accreditation is the highest recognition for municipal and community forestry programs.

Tree Plotter / Aspen Tree Inventory

View the Aspen Tree Plotter

Urban Forestry Analysis Reports

For further information regarding the reports visit i-Tree.

Tree Removal Permit

Tree sizes requiring a Tree Removal Permit, as measured 4.5 feet from the ground surface, are as follows:

Native material that is 3 inch and greater Diameter
Coniferous trees that are 4 inch and greater Diameter
Deciduous trees that are 6 inch and greater Diameter

View the Tree Permit Checklist (PDF).
Review Tree Removal Fees (PDF).
Learn more about the process and apply for a Tree Removal Permit.

CRZ (Critical Root Zone)

In the fall of 2024, the previously used term “dripline” was replaced by the City of Aspen with Critical Root Zone (CRZ), which is now defined in the municipal code. The CRZ more accurately represents a given tree's root structure, simplifying the development process and providing clearer guidelines for builders. The CRZ ensures that tree roots are adequately protected during construction, preserving tree health and reducing damage risks. For more information on the CRZ and how it is measured see the link to the diagram on this page under "Related Info". You may also contact the City of Aspen Forestry team at 970-920-5120 with any questions.

Management Plans

The City of Aspen takes a hands-on approach of ensuring the health and vitality of its community forest and natural resources through the implementation of both a community forest management plan, as well as a noxious vegetation/restoration management plan. These plans give clear definition to the everyday operations carried out by our Department, such as tree pruning, planting, hazard tree identification/monitoring, insect and disease control, restoration or native habitats, upkeep of our cutting edge GIS-based tree inventory program, and tree preservation. The City of Aspen takes pride in the management of the community forest and surrounding open space parcels, going above and beyond management activities of communities of similar size.

It is because of this resource management that the City feels the community forest and the local natural resources will remain intact and vital for generations to come. For more information or a free house visit regarding trees or natural resources, please email City Forester David Coon, or call 970-429-2031.