City comments on your arborist report list the deficiencies the reviewer wants fixed before the file moves forward. Most revision requests are predictable, and knowing what reviewers flag most often means you can fix them in one round rather than three.
What “City Comments” Means
When Toronto’s Urban Forestry department or another GTA municipality reviews an arborist report, a staff member (an urban forestry inspector or plan reviewer) reads it against their internal checklist. If something is missing, measured incorrectly, or documented below the required standard, they issue written comments and return the file to the applicant.
The application stays open. Any time spent preparing and resubmitting a revised report is time your project sits in queue.
Trees Within Six Metres Are the Most Common Flag
The single most frequent comment across GTA construction arborist reports is missing or incomplete coverage of trees adjacent to the property line, specifically trees on neighbouring properties whose root systems or canopy extends within the construction impact zone.
Toronto requires the report to show every tree within 6 metres beyond the limit of site disturbance, including trees on neighbouring properties. The limit of site disturbance includes construction traffic and material storage.
If the report only inventoried your client’s trees and ignored the Norway maple on the neighbour’s lot whose root zone runs under the proposed excavation, expect a comment asking for the adjacent tree to be included, assessed, and addressed in the protection plan. The fix is a site revisit, an updated inventory entry, and a revised protection zone map, which adds a few business days plus whatever time the resubmission takes to re-enter the queue.
Before you submit, walk the perimeter. Every tree whose canopy or root zone could reach the proposed work belongs in the report, on any property.
Tree Protection Plan Scope and Scale
Construction arborist reports need a separate Tree Protection Plan drawing. A written description of the fencing is not enough. Reviewers check:
- That the plan is drawn to scale and includes a north arrow and legend
- That protection zone radii are calculated and shown, not estimated
- That fencing locations do not conflict with proposed grading, servicing, or access routes shown on the building permit drawings
- That the spec addendums (fencing installation details, signage, horizontal protection) are included and match current municipal standards
A common flag is a protection plan that was prepared before the final building permit drawings were issued. If the proposed driveway moved two metres from where it was when the arborist visited, the fencing layout in the report now places barriers inside the proposed work area. The reviewer will catch this because they compare the arborist report to the permit package.
Match the arborist report to the current site plan drawings before you submit. Our construction arborist reports include a Tree Protection Plan that coordinates with your permit drawings, which is why we ask for the site plan before we visit.
Protection Zone Measurement Method
Reviewers will flag a protection zone if the method of calculation is not stated in the report. The two most common methods are a fixed radius multiplier per centimetre of trunk diameter, and a municipal formula that accounts for species and site conditions.
Toronto Urban Forestry expects the report to state which method was used and why. If the arborist used a different calculation than the standard municipal formula because site conditions warranted it, that decision needs to be documented in the report. Reviewers comment on “protection zone as shown on plan” when the report states no method.
If your municipality sets a formula (Toronto’s is in the Toronto permit guide), the report must apply it to every tree in the inventory.
Photo Quality and Documentation
Photograph requirements are the easiest deficiency to avoid and a common flag. Reviewers want:
- Photos that clearly show the base of the trunk where the diameter measurement was taken
- Photos that show the overall crown, taken far enough back to capture the full canopy
- Photos taken in conditions where the subject is visible (not shot into direct sun, not obscured by adjacent shrubs)
- At least one photo per tree, cross-referenced to the tree inventory by tag or numbering system
A common error is submitting photos where it is impossible to tell which tree is which, or where the trunk photos do not show the measurement point clearly. When a reviewer cannot verify the documented condition from the photos, they request better documentation. This requires another site visit.
A second photo set with consistent numbering and orientation notes adds almost no time during the site visit and eliminates a common revision round.
How Revision Rounds Work
When comments come back, the process is:
- The city sends written comments to whoever submitted the application (the property owner or their agent).
- The arborist prepares a revised report addressing each comment. The revision letter answers each comment in order.
- The revised package (updated report, revised plan, response letter) is resubmitted through the same channel as the original application.
- The reviewer re-checks the file. If all comments are addressed, the application proceeds. If new issues surface or a comment was only partially addressed, a second round of comments is issued.
A straightforward revision round adds two to four weeks. Projects under construction permit timelines cannot absorb multiple rounds.
The fastest way through a revision is a detailed response letter that quotes each comment, confirms the change made, and cites the page and paragraph in the revised report where the reviewer can verify it. If the reviewer has to hunt for a change, expect a follow-up comment on something you already fixed.
When the Report Type Is Wrong
Some comments are about the document’s scope. A reviewer can say the submitted report covers tree removal but the project also needs a construction impact assessment and protection plan, or the reverse.
If you submitted a tree removal report for a project that involves construction near retained trees, the city needs a separate construction arborist report before the building permit can proceed. The resources page on which report you need covers the distinction in detail.
A wrong report type is the slowest revision request to fix, because the fix is a new document. Pick the report type before you submit.
Preventing Comments Before Submission
Check these items before you submit an arborist report for a construction project:
- Read the municipality’s current arborist report requirements before the site visit. Urban Forestry updates its criteria, so your last project’s standard can be out of date.
- Share the current building permit drawings with the arborist before the site visit, not after.
- Check that every tree within 6 metres beyond the limit of site disturbance, on any property, is assessed and included.
- Confirm that the protection zone methodology is stated explicitly for every tree.
- Number photos and cross-reference them to the inventory table.
If the report is being prepared for Toronto specifically, Toronto’s checklist asks for specific items: a landscape and replanting plan with a stated minimum stock size (50 mm caliper for deciduous trees, 1.75 to 2.5 m height for conifers), a separate Tree Protection Plan, protection zones plotted to scale with hoarding distances on the site plan, trees numbered to match the report, a signed and witnessed Undertaking and Release, and the City’s own Guidelines for Completion of an Arborist Report. A report built for another city’s template draws comments in Toronto when it misses these.
Two Rounds Means the Report Has a Problem
One revision round is normal on complex sites. Two or more rounds point to a structural problem with the original report, either in how the site was assessed or how the documentation was organized.
If you are already in a revision cycle and the comments are not resolving after two rounds, have a different ISA Certified Arborist review the report and the city’s comments before you resubmit.
We revise reports prepared by others, and we prepare full reports from site visit through final approval. See the construction reports service page for details on turnaround and pricing.