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The purpose of this procedure is to outline the required action to protect trees during construction. This procedure shall represent the standard specifications for tree protection whenever tree protection measures are required by the Town. Higher standards of tree protection may be imposed where warranted in the opinion of the Town having regard to the size, variety, location and health of the tree, and any circumstances surrounding the construction which requires additional tree protection measures.
This procedure applies to Town and private trees covered under any municipal permit process or agreement relating to construction.
Town trees required to be removed as a result of construction activities must receive approval by the Town Forester or designate. If approval is granted for removal of Town owned trees, the applicant will assume all costs involved and shall either: 1) pay the amenity value of the tree(s) calculated in accordance with the most recent International Society of Arboriculture Guide for Plant Appraisal; or 2) plant the equivalent number of trees based upon a “no net loss or canopy cover” objective as determined by the Town Forester or designate. Where tree relocation is approved, the applicant will assume all relocation and establishment costs.
Anyone failing to adhere to this procedure will be financially responsible for any resulting damage to trees in addition to any penalty that may be imposed under relevant by-laws or statutes.
The Tree Protection Zone (TPZ) is the minimum setback required to maintain the structural integrity of the tree’s anchor roots, based on generally accepted arboricultural principles. If trees are protected to the TPZ then the tree’s anchor root structure is expected to be maintained.
No unauthorized activities may take place within the TPZ of a tree covered under any municipal permit process or agreement. The following chart shows the TPZ. Some trees and site conditions may require a greater setback at the Town’s discretion2
Diameter of Trunk (DBH)2 in centimetres |
Tree Protection Zone3 Distance from trunk measured in metres |
<10 | 1.8 |
10-30 | 2.4 |
31-50 | 3.0 |
51-60 | 3.6 |
61-70 | 4.2 |
71-80 | 4.8 |
81-90 | 5.4 |
91-100 | 6.0 |
Trees within or adjacent to a construction site must be protected during construction by means of a barrier installed in accordance with the table in section 1 and meet the following specifications:
Tree Protection Zone
No grade change, storage of materials or equipment is permitted within this area. |
For trees covered under this procedure, written authorization from the town is required in the form of either a Tree Protection Agreement, or a Tree Protection Zone Encroachment Permit or a Tree Permit; and
The applicant is required to have a town approved tree service raise the crown of all branches to provide adequate clearance for construction equipment.
3.1. Tree Protection Agreement (TPA)
The applicant is required to enter into a Tree Protection Agreement when construction activities take place outside of the TPZ area as determined by Town Forester or designate. Should the town determine that a tree protection agreement is required, a tree protection agreement fee shall be charged to the applicant in accordance with the established town fees
3.2. Tree Protection Zone Encroachment Permit (TPZEP) - Schedule 2 (Application)
3.3. Tree Permit (TP)
Where the impact on the structural integrity of anchor roots is beyond acceptable limits and may cause a hazardous tree:
An Arborist Report is required: where multiple trees are involved in a Capital Project, a Municipal Consent, and/or a planning application; and an Arborist Report is mandatory to initiate a Tree Protection Zone Encroachment Permit or a Tree Protection Agreement.
Arborist report must be signed by a Registered Professional Forester as defined in the Ontario Professional Foresters Act where the construction has a potential impact on woodlands.
An Arborist Report shall be prepared by an Arborist and must include but is not limited to the following:
The Town may request additional information in an arborist report for Capital projects, Municipal Consents, and planning applications at the discretion of the Town.
A Tree Protection Plan is required for site plan and site alteration applications at the determination of the Town. Such plans shall include but are not limited to the following:
The town may request additional information in the tree protection plan for planning applications at the discretion of the town.
Where tree protection measures are required as a condition of any agreement, approval or permit, the Town will require securities to secure the protection of trees. The required securities, as determined by the Town shall be held by the Town for a period specified by the Town. Early release of securities may occur provided the Town is satisfied that the tree has not been damaged. Applicants requesting for the early release/reduction of securities or final release shall submit for approval an Audit from an arborist certifying that the tree is in a state of vigorous health and has not been injured or destroyed as a result of the construction activities in accordance with section 7 below.
Tree Protection Audits prepared by an arborist are required for all trees present or adjacent to a construction site when activity, or the potential for activity, takes place within the TPZ. A schedule of audits by an arborist will be specified at the discretion of the Town and shall consist of a minimum of three written site inspection reports. These tree protection audits shall include the following:
Failure to comply with this procedure may result in one or more of the following:
Arborist: means a person who has graduated from an accredited college or university with a diploma or degree in Urban Forestry, Arboriculture or equivalent and satisfies at least one of the following requirements:
Hazardous Tree: means a tree that is destabilized or structurally compromised such that it poses a potential safety concern to property or life.
Woodlands: means as defined in the Halton Region Tree By-Law 121-05, as may be amended or replaced, namely: an area of land with at least: 1000 trees, of any size, per hectare or 500 such trees per 0.5 hectare; 750 trees, measuring over five (5) centimetres in diameter at DBH, per hectare or 375 such trees per 0.5 hectare; 500 trees, measuring over twelve (12) centimetres in diameter at DBH, per hectare or 250 such trees per 0.5 hectare; or 250 trees, measuring over twenty (20) centimetres in diameter at DBH, per hectare or 125 such trees per 0.5 hectare; but does not include: an active cultivated fruit or nut orchard; a planation established for the purpose of producing Christmas trees; a plantation specifically planted and maintained for the purpose of harvesting as certified in writing by an Officer based on field inspection and investigation; a tree nursery, or a narrow linear strip of trees that defines a laneway or a boundary between fields.
Procedure Number: EN-TRE-001-001
Parent Policy: EN-TRE-001
Section: Environment
Sub-Section: Trees
Author: Forestry Section, Parks and Open Space and Development Services Department
Authority: CAO
Effective Date: 2009 May 04
Review by Date: 2021
Last Modified: 2016 Nov 14
Town Tree Protection By-law
Private Tree Protection By-law
Site Alteration By-laws
Halton Region’s Tree By-Law 121-005
Halton Region's Tree By-law Frequently Asked Questions
Healthy Green Space for Public Lands Report
EN-GEN-001 Environmental Sustainability policy
Schedule 1: Tree Protection Barrier
Schedule 2: Application for Tree Protection Zone Encroachment Permit
Schedule 3: Tree Protection Plan Form
Schedule 4: Detail TP-1: Tree Protection During Construction