Tree Preservation Information

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An Arborist is defined in Richmond Hill's Tree Preservation By-law as: 

  • an Arborist qualified by the Ministry of Training Colleges and Universities, Apprenticeship and Client Services Branch
  • an Arborist certified by the Certification Board of the International Society of Arboriculture
  • a Consulting Arborist registered with the American Society of Consulting Arborist
  • a Registered Professional Forester (R.P.F.) as defined by the Professional Foresters Act S.O. 2000
  • a person with other arboriculture, forestry or ecology qualifications as approved by the Commissioner of Planning and Infrastructure 

You must retain an Arborist and submit an Arborist Report to Richmond Hill's Planning and Infrastructure Department with your application for a Permit to Injure or Destroy (a) Trees(s).  

Arborist Reports

An Arborist Report is a technical report that identifies the species, size and condition of tree(s), provides reasons for any proposed injury or destruction, and describes tree protection measures or other mitigating activities to be implemented. It should detail specific and accurate information about the tree(s) in question including location, condition, structural integrity, life expectancy, disease, infestations and vigour. It also identifies the nature of the tree work to be undertaken and appropriate protection. 

The Arborist Report must include specific information in both drawing and text format.

Arborist Report Text and Drawings

The Arborist report must include:

  • a summary of arboricultural evaluation methods used to catalogue and assess the tree(s)
  • the date and time of site inspections conducted to facilitate completion of the Arborist Report
  • descriptions of the tree(s) identified on the Arborist Report drawing (linked to the drawing and the corresponding tree identification numbers and tags*) including: species (scientific and common name), size (DBH), health (a general rating of poor, fair or good based on tree age, presence of disease, canopy structure, proportion of live wood, etc.), condition (a general rating of poor, fair or good based on the presence of cavities, decay, broken limbs/trunk, lean, root damage, form, etc.)
  • a recommendation as to whether each tree or grouping of trees identified on the drawing should be preserved, removed or transplanted and the reason for each recommendation
  • details as to when and how any recommended trans­planting will be undertaken (including location to which the tree is to be moved, specific techniques to be used, and approximate timing of transplant)
  • details for recommended tree preservation measures which conform to, or are consistent with, Planning and Infrastructure Details and Specifications
  • recommendations for the maintenance and manage­ment of trees to be preserved (i.e. required pruning, fertilization or cable work)

Note: Tagging must not cause any injury to endangered or rare species.

A drawing of the site printed to a sheet not exceeding 60 X 100 cm (24 X 40) inches and illustrating: 

  • the surveyed location of the tree(s) for which the application is being made
  • an indication as to whether the tree(s) is/are recommended for preservation, transplant or removal
  • grading changes, structures and work areas/zones associated with the application
  • the location of any recommended tree preservation measures to be installed

The drawing must include the following information:

  • name, credentials and contact information (address, phone number, company name etc.) of the Arborist who prepared the report
  • name under which the application is submitted and contact information
  • municipal address of the subject property
  • key map (approximate scale of 1: 10 000) in the top right corner of the drawing indicating the location of the site in relation to a larger area (at least one major intersection should be visible)
  • scale of the drawing (between 1: 200 and 1: 1 000) complete legend/key
  • date of preparation/submission
Arborist Certificates

To ensure that you are complying with the requirements, you must submit an Arborist Certificate to the City of Richmond Hill Planning and Infrastructure Department before you make any alteration to a dead, hazardous or diseased tree or as a follow up to emergency work.  

The Arborist Certificate must be signed by an Arborist and must include the following information:

  • the address of the property on which the tree is located
  • contact information for the owner of the property on which the tree is located (name, address, phone number, facsimile number and email address)
  • a description of the location of the tree within the property
  • a description of the tree including species, DBH, approximate height, and condition
  • a photograph of the tree
  • a recommendation for action/ maintenance work in light of the condition of the tree
  • approximate timing of any recommended actions/maintenance work
Arborists Role in the Five-Stage Development Process

Richmond Hill's Tree Preservation By-Law 41-07 protects trees on private property with a trunk diameter at breast height (DBH) of 20 cm or greater. This By-law is an important part of the City's strategy to preserve our urban forest for the benefit of the community. To achieve this, Richmond Hill works collaboratively with developers to protect trees, where possible, during all development stages. Anyone applying for site plan or subdivision approval must submit a tree inventory and preservation plan prepared by an arborist. This plan provides the basic information Richmond Hill needs to assess the impact of development on the existing trees and to ensure trees worthy of keeping are sufficiently protect during construction.  

Five-stage Development Process 

Planning Stage 

What Richmond Hill expects: 

  • Richmond Hill recommends developers hire an Arborist to complete a preliminary tree evaluation at the start of their project. This evaluation should identify trees listed as endangered species, as well as other significant trees on the site, that could constrain the limits of development. Identifying trees for protection at the start of the project will influence decisions regarding site grading, the location of servicing and other subgrade works, and possibly the building envelope. This initial evaluation may also identify trees that could be relocated elsewhere within the site.
  • Trees worthy of retention should have minimum tree protection zones shown on a plan (see chart below) and be used as a design constraint. 

Trunk Diameter

Tree Protection Zone

<10 cm

1.8 m

11-40 cm

2.4 m

41-50 cm

3.0 m

51-60 cm

3.6 m

61-70 cm

4.2 m

71-80 cm

4.8 m

81-90 cm

5.4 m

91-100 cm

6.0 m

Arborist's role:

  • Arborists prepare plans that show numbered trees that are cross-referenced to an assessment table. The table provides information about the species, size, condition and required pre and post- development maintenance. Other information may include recommendations for preservation or the removal of trees based on condition and species. For retained trees, the Arborist should include recommendations for further possible works, e.g. pruning and deadwooding, etc. For forested sites, the Ministry of Natural Resources Forest Inventory Resource Mapping may be used as a resource (species breakdown percentages by area).
  • Plans should also identify trees on neighbouring properties within 6 m of the boundary.
Design Stage

What Richmond Hill expects: 

  • Trees worthy of retention should be considered a design constraint.
  • A revised tree preservation/tree relocation plan and timing schedule for activities and site visits by an Arborist, for future reference must be provided.
  • Once the design and tree preservation plans are approved by the City, a valuation of trees will be required from the Arborist.

Arborist's role:

  • Arborists advise the design team on the viability of retaining trees as related to the grading, soil storage, construction access, vehicle manoeuvring, servicing, drainage implications, height restrictions and material storage, etc.
  • Preliminary plans should be circulated to an Arborist for comment. Direction can be provided with respect to grading and servicing plans as needed.
  • Arborists advise the design team on the protection of trees on neighbouring properties. 
  • Tree Protection Zones (TPZ) for trees on abutting properties should be considered a design constraint. Arborists can provide specifications for TPZ, as well as proposed pruning or other work as needed based on siting of buildings and services. The developer is required to notify the adjacent property owners of any intended work and seek cooperation in advance of it being carried out.
  • Arborists also advise on soil mitigation, irrigation, pre-emptive pruning, tree protection fencing and sediment control fencing.
  • Arborists should provide information on which plans, plan numbers and revisions of developer's plans were used in the Tree Preservation Plan submission.
Pre-Construction Stage

What Richmond Hill expects: 

  • The developer should meet with City representatives to agree on TPZ layout and timing of the installation/tree relocation.
  • The developer should stake out and install tree protection fencing/sediment control fencing on site.
  • The developer should install TPZ signage on TPZ fencing. The signs should include contact details for the Arborist and details of the valuation of the trees. The Arborist should advise the City when installation is complete. the City may visit the site to validate.
  • Remove trees as shown on the approved tree preservation plan that are not for retention.

Arborist's role:

  • Arborists can ensure tree preservation, removal, installation and relocation during the pre-construction, is completed in accordance with approved drawings.
Construction Phase

What Richmond Hill expects: 

  • All measures to protect and preserve existing trees should be maintained and in good working condition to ensure the health and survival of the trees.

Arborist's role:

  • Arborists should record all site visits and certify/verify that tree protection/tree relocation is effective during all phases of construction for future reference.
  • Arborists should notify the City of any non-compliance with the approved tree preservation plans. Any resolutions to correct the non-compliance issue(s) should involve the Arborist and be approved by the City before implementation.
  • Arborists should certify that tree protection measures have been implemented throughout the project in accordance with the approved drawings and reports.
Post-Construction Phase
 What Richmond Hill expects: 
  • Once construction is complete the Arborist should check to see if there are tree-related issues before the TPZ fencing is removed. Any tree work required at this stage should occur before the final grading and sod application.
  • Arborists should continue monitoring the health of trees and make recommendations for ongoing work to mitigate the stress from construction such as remedial pruning, irrigation, deep root feeding, TPZ barriers/fencing removal, etc. (recommended for 3 years after construction is complete).
  • Prior to applying for Subdivision Assumption or reduction of securities, an Arborist should visit the site to review the trees and note any changes since previous visits. If there are significant grade alterations or damage to trees, the Arborist should contact the City for further review and direction.
  • Between Assumption and End of Maintenance (final release of Landscape Letter of Credit), an Arborist should visit the site at least twice during the growing season to determine if there are any changes to the health of the trees. At this point, the Arborist should make any final post-construction tree works recommendations that would ensure the long-term health and vitality of the trees.
  • When applying for End of Maintenance, an Arborist should visit the site to identify any tree health issues and make arrangements for appropriate action at the developer's expense. Arborists are required to sign-off on all tree-related issues prior to staff's request that Council support the developer's End of Maintenance request. Arborists should submit to the City records of all project- related visits, inspections, instructions and completed work. Any tagging should be removed at the End of Maintenance stage, as directed by the City.
Other Things to Consider
  • Species of trees listed on the Endangered Species Act 2007 are protected at any size. The destruction of these species is subject to severe penalties.
  • Richmond Hill's Street Tree By-law 40-07 protects trees on the City's Public Road Allowances.