City comments on your arborist report are not a rejection. They are a checklist of specific deficiencies that the reviewer wants addressed before the file can move 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” Actually Means
When Toronto’s Urban Forestry department or another GTA municipality reviews an arborist report, a staff member (typically 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. Your permit clock does not reset. But any time spent preparing and resubmitting a revised report is time your project sits in queue.
Toronto does not publish a standard review time in its current application guidance. Any time spent preparing and resubmitting a revision still extends the project timeline. That matters on construction projects where every week has a carrying cost.
Trees Within Six Metres: 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.
Most municipalities require the report to address any tree whose trunk is within a set distance of proposed construction. For construction-related reports, that commonly means trees on adjacent properties whose protection zone overlaps the work area, not just trees on the subject property.
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 typically adds a few business days plus whatever time the resubmission takes to re-enter the queue.
The practical lesson: before submitting, walk the perimeter and confirm that every tree whose canopy or root zone could reasonably interact with the proposed work is in the report, regardless of whose property it sits on.
Tree Protection Plan Scope and Scale
Construction arborist reports require a separate Tree Protection Plan drawing, not just a written description of where fencing should go. 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 may now place barriers inside the proposed work area. The reviewer will catch this because they compare the arborist report to the permit package.
Aligning the arborist report with the current site plan drawings before submission is the fastest way to avoid this specific comment. 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. “Protection zone as shown on plan” without a stated methodology is a comment waiting to happen.
If your municipality uses a specific formula (thresholds vary; see the Toronto permit guide for Toronto-specific details), the report must demonstrate that formula was applied consistently across every tree in the inventory.
Photo Quality and Documentation
Photograph requirements are the easiest deficiency to avoid and one of the more common flags in practice. What 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 (typically the property owner or their agent).
- The arborist prepares a revised report addressing each comment. Comments are usually numbered; the revision letter should respond to each one 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.
Most straightforward revision rounds add two to four weeks, depending on the city’s current queue depth and how quickly the arborist can turn around the revised report. Projects under construction permit timelines often 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. Forcing the reviewer to hunt for the change in a revised document without guidance adds friction and risks a follow-up comment on something that was actually fixed.
When the Report Type May Be the Problem
Sometimes the comment is not about a specific deficiency but about the scope of the document itself. A reviewer may indicate that the submitted report addresses tree removal but the project also requires a construction impact assessment and protection plan, or vice versa.
If you submitted a tree removal report for a project that involves construction near retained trees, the city may require a separate construction arborist report before the building permit can proceed. These are two different documents with different purposes, and municipalities treat them separately. The resources page on which report you need covers the distinction in detail.
Getting the report type right before submission avoids the most time-consuming category of revision request, because the fix is not a revision, it is a new document.
Preventing Comments Before Submission
The practical checklist before submitting any arborist report for a construction project:
- Confirm the municipal requirements with the building department, not just with standard practice. Requirements shift as municipalities update their standards, and the review team at Urban Forestry may apply criteria that are more current than what was standard on your last project.
- Share the current building permit drawings with the arborist before the site visit, not after.
- Verify that all adjacent trees within the relevant distance have been 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, the Urban Forestry department’s internal review standards are more detailed than most other GTA municipalities. Reports that pass review in Markham or Richmond Hill may still generate comments in Toronto if they do not meet the documentation depth that Toronto reviewers expect.
Getting to Approval Faster
One revision round is normal on complex sites. Two or more rounds usually indicate 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, it may be worth having the report reviewed by a different ISA Certified Arborist before resubmitting. A fresh read of both the city’s comments and the current document will often find what is being missed.
Our team handles revision support for reports originally prepared by others, as well as full report preparation from site visit through final approval. See the construction reports service page for details on turnaround and pricing.