Special tree categories are used by communities to identify, protect and promote the trees of highest value in their community forest through regulations in the tree ordinance.
Tree ordinances in Georgia include many special tree categories. Georgia communities value large, landmark, historic, heritage, native, ornamental, and unique trees and therefore regulate the management of these trees in their tree ordinances.
Common tree categories defined in Georgia tree ordinances are listed below, along with the number of communities that use the tree category.
- Specimen trees, 82 communities, usually trees of certain species or types, and of a minimum DBH
- Protected trees, 18 communities, trees that must be protected and require permitting or approval to disturb or remove
- Exceptional trees, 10 communities
- Heritage trees, 10 communities, may be historic or landmark in addition
- Landmark trees, 10 communities, usually individual trees or tree groups that are widely known within the community
- Significant trees, 9 communities
- Historic trees, 8 communities, usually associated with an historic event, person or place
- Official tree species, 7 communities, signature tree species of the community
Some other tree categories are included for the purpose of maintaining or increasing tree species diversity or tree canopy cover. These categories include:
- Understory trees, trees typically found in the lower parts of the forest canopy that have small heights and canopies, providing only minimal shade
- Shade, canopy and overstory trees, trees typically found in the upper parts of the forest canopy that provide significant shade
- Native and non-native trees
- Ornamental trees, usually flowering trees
Communities may limit the amount of trees that can be planted on a site from one of these categories (non-native, ornamental), or require that a minimum amount of the trees planted or retained on a site be from one of these categories (overstory, shade, native).
The tree category most often defined in tree ordinances in Georgia is specimen tree. At least 82 cities and counties define specimen trees in their ordinances and include regulations to conserve and protect these tree. Click here to see a list of these communities.
There is no single definition of a specimen tree, but generally specimen trees are defined by their species or type and must meet minimum DBH requirements. The definitions vary significantly from one community another because communities differ in the value they place on certain tree species, tree sizes, and special tree characteristics, as shown below in the chart of some community examples.
Usually included in the definition of a specimen tree is the requirement that the tree have a life expectancy of 15 years, and be in fair or better health and sound structural condition.
Communities often define specimen tree stands in addition. The basic criteria for a specimen tree stand are:
- A relatively mature even-aged stand
- A stand with purity of species composition or of a rare or unusual nature
- A stand of historical or cultural significance
- A stand with exceptional aesthetic quality
Specimen trees are usually given extra credit when they are conserved, commonly two times the standard unit value. When they are approved for removal, they must be replaced inch-for-inch, or their unit value must be replaced, or in many cases they must be replaced at 2 or 3 times their unit value, usually with larger caliper trees than normally required (3-inch or 4-inch caliper). A system of recompense is also in place in many communities, requiring a payment into the tree fund to compensate for the loss of the tree, if replacement on site is not feasible.
When specimen trees are damaged during construction or removed without permission, many communities require that they be replaced, again with larger caliper trees, in amounts up to 8 times their unit value!
Protected tree is a collective term for trees from one or more of the special tree categories and other trees, such as public trees or trees above a minimum DBH on private property. The disturbance or removal of protected trees is regulated in tree ordinances, either through the tree removal permitting process or tree plan approval process.
This category includes criteria similar to that for the significant tree category described below.
Exceptional trees are similar to landmark and heritage trees in that they must be nominated by the property owner, and approved by the tree board and/or the city council or county commission. They may or may not have a minimum DBH requirement, but must meet quality requirements such as those cited in Vidalia’s tree ordinance, in Section 6-114. – Designation of Exceptional Trees, in Division 3. – Tree Protection and Tree Establishment, Article IV. – Land Clearing and Tree Protection, Chapter 6 – Buildings; Construction and Related Activities, as follows:
- The tree is demonstrated to have an association with a documented historical event, or is located on an historic site
- The tree has unusually high aesthetic value
- The tree is of unique character because of its age, species, variety, location, or because of the size and development of its crown, trunk, or main stem
- The tree is free of disease, pests or serious injury
- The tree has a life expectancy of more than ten (10) years
- The tree is free from structural defects which could present a hazard to the public
Moultrie includes a minimum diameter in their definition of exceptional tree in Section 114-34. – Exceptional Tree Criteria, in Article II. – Trees, Chapter 114 – Vegetation, as follows:
A tree may be declared an exceptional tree if it is in fair or better condition and capable of delivering at least 75 percent of foliage to the scaffolding branches that equals or exceeds the following diameter sizes: Large trees 40 feet or more in height at maturity, e.g. oaks, hickories, yellow poplars, sweetgums, long leaf pine, sycamore, etc. with a 20 DBH.
Heritage trees are similar to exceptional trees and landmark trees in that they must be nominated by the tree owner and approved by the tree board and/or the city council or county commission. The arborist or forester keeps a registry of heritage, exceptional or landmark trees. These trees are often given special consideration during development, with additional credit given if they are conserved, and additional replacement required if they are removed.
Landmark trees are designated by communities through a nomination process of the tree board and approval by their city council or county commission. These are trees that meet special criteria for age, size, historical significance,
A landmark tree is defined by the Georgia Urban Forest Council (GUFC) as a tree that is an integral part of an individual community and its heritage. The GUFC has a Landmark and Historic Tree Register that further defines their criteria for designating trees in these categories.
At least 10 communities in Georgia define landmark trees in their tree ordinance, and in fact a few reference the GUFC’s Landmark and Historic Tree Register in the ordinance.
Communities may define and regulate more than one of these categories of trees, and put them in a collective category such as protected tree (described above) or significant tree. For example, Forsyth County defines significant trees that include specimen, historic and landmark trees, in Section 86-62. – Significant Trees, in Division 2. – Applicability and Permitting, Article II. – Tree Protection and Replacement, Chapter 86. – Vegetation.
Historic trees are defined in the GUFC’s Landmark and Historic Tree Register program as trees that are important to the culture and history of the state or nation. Trees important to the culture and history of a community would also be considered historic trees within that community.
Historic, heritage, exceptional, and landmark trees are similar categories of trees with similar requirements for their nomination, designation and registration.
OFFICIAL TREE SPECIES
In Georgia, at least 7 communities establish an official city tree in their tree ordinances. The cities and their official tree species are:
- Atlanta – Flowering Dogwood (Cornus florida)
- Bainbridge – Live Oak (Quercus virginiana)
- Columbus – Muskogee Crapemyrtle (Lagerstroemia indica ‘Muskogee’)
- Hinesville – Live Oak (Quercus virginiana)
- Jesup – Flowering Dogwood (Cornus florida)
- Rincon – Flowering Dogwood (Cornus florida)
- Waycross – Eastern Redbud (Cercis canadensis)