Technical Standards

A significant amount of effort, time and money are required to develop, administer and implement a tree ordinance.  The positive result of expending these resources can be maximized by including in your tree ordinance requirements for compliance with professional standards for tree care operations.

Quality tree conservation, protection, and establishment will:

  • Conserve a greater amount of healthy tree canopy
  • Reduce conserved tree death and decline due to damage during construction or everyday activities
  • Improve survivability of newly planted trees
  • Reduce the need to replace recently planted trees and conserved trees that have died or in decline to meet tree density requirements
  • Save time, effort and money!

Your set of technical standards should include:

  • Standards and best management practices for tree care operations
  • Construction details and specifications
  • Approved tree species list


Technical standards and best management practices for tree care operations are available from the International Society of Arboriculture (ISA).  The standards have been developed by committees of arboricultural professionals and adopted by the American National Standards Institute (ANSI).  ISA has produced best management practices that further clarify the standards in a user friendly format.

The following standards and best management practices can be purchased through the ISA store:

  • ANSI Z133.1 Safety Requirements (also available in Spanish)
  • ANSI A-300 Standards for Tree Care Operations
    • Part 1 Pruning
    • Part 2 Soil Management, a. Modification, b. Fertilization, c. Drainage
    • Part 3 Supplemental Support Systems
    • Part 4 Lightning Protection Systems
    • Part 5 Management of Trees and Shrubs During Site Planning, Site Development, and Construction
    • Part 6 Planting and Transplanting
    • Part 7 Integrated Vegetation Management, a. Utility Rights-of-way
    • Part 8 Root Management
    • Part 9 Tree Risk Assessment, a. Tree Failure
    • Part 10 Integrated Pest Management
  • Best Management Practices
    • Integrated Pest Management
    • Integrated Vegetation Management
    • Managing Trees During Construction
    • Root Management
    • Soil Management
    • Tree and Shrub Fertilization
    • Tree Injection
    • Tree Inventories
    • Tree Lightning Protection Systems
    • Tree Planting (also available in Spanish)
    • Tree Pruning (also available in Spanish)
    • Tree Risk Assessment
    • Tree Support Systems
    • UAA
    • Utility Pruning of Trees (also available in Spanish)

A download of the ANSI Z60.1 Standard for Nursery Stock is available through the AmericanHort website.

You should reference these arboricultural standards and best management practices in your tree ordinance, as well as include your own standards and specifications.  A current copy of each of the ANSI standards and ISA best management practices, and any other standards you require, should be kept on file in the office of the tree ordinance administrator, or the city or county clerk, and made available for use by individuals and companies tasked with implementing and complying with the ordinance regulations.

If you include your own standards and specifications, make them basic and concise.  Include the least amount of standards that will accomplish your goals.  And, include only those standards that you are prepared to enforce.


You can provide standard construction details, and specifications, for tree protection, planting, staking, and mulching to facilitate the proper installation of tree protection fencing and tree protection signs around existing trees that will be conserved, and for the installation of new trees.  The construction details are available and can be provided in PDF or DWG files to the development and construction communities for inclusion on site plans, tree conservation plans, and tree planting plans, along with specifications in PDF or Microsoft Word format.

Online sources of construction details and specifications available in various formats are listed below.  You can search online for additional construction details and specifications from other communities using the Municode library.


The tree species list is a tool that helps a community control the size, quality and placement of trees in their community.  Communities can also control the planting of invasive or exotic species that are unsuitable in the landscape through their tree species lists.

This control extends only to tree planting, and conservation in some cases, done to satisfy the requirements of the tree ordinance.  The list is not applicable to the planting of trees for reasons and in places outside of tree ordinance requirements.  Property owners who want to plant a tree on their property do not need to comply with the tree species list, but it can be used by them to guide their tree planting decisions.

Almost every tree ordinance includes a list of approved tree species, either in the body of the ordinance or as a supplement in an administrative or technical standards or guidelines document.  This list usually includes the species common name, Latin name, and tree size.  Tree size usually refers to the height the tree will attain at maturity, and is listed either by size category or a range of maximum height in feet.  Lists are often arranged by tree size category, such as small trees, medium trees, and large trees or overstory trees and understory trees.

The tree species list has great value in educating the user in which species will perform well, and in what locations.  Some lists include the approved locations for a species–such as beneath overhead utility lines, in utility corridors, in parking lot islands, in large landscape areas, as street trees in tree lawns, or near drainage structures or riparian areas.

There are several good sources of information on tree species, and on species suitable for planting in Georgia communities.  The Athens-Clarke County Tree Species List is one of the most extensive lists developed for use with a tree ordinance, and it includes both native and non-native species suitable for planting in north Georgia.

The City of Atlanta Tree Planting List categorizes trees by overstory and understory size categories, and also list trees for specific locations and purposes such as screening, narrow spaces, detention ponds and wetlands, road frontages and parking lots.

There are several other good sources of information on tree species recommended for planting in Georgia, and for not planting:


You may also want to include some administrative standards in your tree ordinance that describe the processes to be used in permit applications, plans review and inspection and enforcement.  Many communities includes forms that are required to be used in these processes, and checklists that can facilitate compliance with ordinance requirements.