Heritage trees are a distinctive feature of the Walnut Creek Neighborhood and add considerable value to our property. The City of Austin provides support for the preservation and appropriate care of heritage trees citywide. For easy reference, these are some of their requirements.
HERITAGE TREE means a tree that has a diameter of 24 inches or more, measured four and one half feet above natural grade, and is one of the following species:
(a) Ash, Texas
(b) Cypress, Bald
(c) Elm, American
(d) Elm, Cedar
(e) Madrone, Texas
(f) Maple, Bigtooth
(g) All Oaks
(i) Walnut, Arizona
(j) Walnut, Eastern Black
Requirements for Preservation
Tree & Natural Area Preservation
The City of Austin Tree and Natural Area Preservation code is based on the fundamental precepts of sound urban forest management. Proposed development projects are evaluated on a case-by-case (and tree-by- tree) basis, which entails evaluating the existing tree resources on a site, understanding the dynamics of trees and development impacts, and negotiating a solution that results in a development with a balanced mixture of tree species and age. The goal of each review is to assure that, through a combination of preservation and re- forestation, a final product is achieved which results in a diversified and sustainable urban forest.
Trees 19 inches in diameter (60 inches in circumference) and greater are classified as “protected size” and receive enhanced preservation evaluation. Protected trees require a permit to remove them, impact the critical root zone (i.e. utility trench, sidewalk, driveway, irrigation lines, foundation), or remove more than 30% of the canopy.
Critical Root Zone (CRZ):
One foot from the tree trunk for each diameter inch of trunk size.
Environmental Criteria Manual Tree Preservation Design Criteria
◄3.5.2 Critical Root Zone Impacts –
A tree’s root system ranges well beyond the dripline. The CRZ has been established to set a practical limit beyond which any loss of roots would not have a significant impact on a tree’s survival. Design constraints often dictate that trees slated for preservation have some encroachment on their critical root zone. Weighing this fact with what appears to be an acceptable degree of risk to most trees, the following minimum design criteria (maximum allowable impacts) have been established:
* A minimum of 50% of the CRZ must be preserved at natural grade, with natural ground cover, and
* No cut or fill greater than four (4) inches will be located closer to the tree trunk than the 1⁄2 CRZ.
Example: a tree with a 20-inch diameter trunk has a 20-foot CRZ, and a 10-foot 1⁄2 CRZ.
In order to assure that trees are adequately preserved, tree protection fencing is required for trees within the limits of construction. Fencing should protect the entire Critical root zone (CRZ) area. Fencing is required to be chain-link mesh at a minimum height of five feet. A 6-inch layer of mulch within the entire available root zone area is required for trees which have any disturbance indicated within any portion of the critical root zone.
Trunk Measurements►Diameters of tree trunks are measured at 4 1⁄2 feet above grade. If the tree is on a slope, measure from the high side of the slope. Measure above or below unusual swells in the trunk. To determine the diameter of a multi-trunk tree, measure all the trunks; add the total diameter of the largest
trunk to 1⁄2 the diameter of each additional trunk.
For more information visit www.ci.austin.tx.us/trees or contact the City Arborist at (512) 974-1876 or Michael.Embesi@ci.austin.tx.us.
The following is a standard email response when someone is requesting to remove or impact a protected tree due to proposed development:
Thank you for contacting the City of Austin. Please complete the attached application to initiate the tree review process. After receiving the application, an assessment of the proposal and tree typically takes one week to perform. The attachments also include particulars associated development regulations. Additionally, the following four minute video may assist you with understanding of the tree permitting process: http://www.youtube.com/watch?v=lezcvjwoRdY.
The following statements are from the COA website (www.cityofaustin.org/trees) if someone suspects illegal tree removal:
Reporting Illegal Tree Removals
Is someone cutting down a large tree in your neighborhood and are you unsure if they have a permit? You can first check here (https://www.austintexas.gov/devreview/a_queryfolder_permits.jsp) to see if they have a permit: If they do not, then contact 311, email us any time via the email hotline. The message will be received, even on the weekends.