Get Involved

Anyone can help — from spotting an error to managing the whole map. Pick the role that suits you.

Spotter
No account needed

Spotted a wrong species, an outdated measurement, or a missing detail? Submit a correction directly from the map — no signup required.

  • Suggest edits to existing trees
  • Submit species, DBH, height, or location corrections
  • Leave notes and comments on a tree
  • Add new trees (Mapper only)
  • Edits go live immediately (pending review)
Submit a Correction
Mapper
GitHub account required

Trusted contributors with admin access. Edits go live immediately — no waiting for approval. Ask a Steward to add you.

  • Edit any existing tree in real time
  • Add new trees to the map
  • Delete duplicate or incorrect entries
  • Commits attributed to your GitHub profile
  • Add other Mappers (Steward only)
Ask to Become a Mapper
Steward
GitHub account required

Stewards manage the community — they can grant Mapper access to trusted contributors and keep the data clean.

  • Everything a Mapper can do
  • Add and remove Mappers
  • Review and approve Spotter suggestions
  • Access the GitHub user management panel
View Repository

Roles stack upward — Mappers can do everything Spotters can, Stewards can do everything Mappers can.

Suggest

Edit a tree

Found a wrong species, missing detail, or outdated measurement?

Open Edit Form
Review

Pending edits

See open Spotter suggestions waiting for a Mapper to review.

View Open Issues
Embed

Embed the map

Add the Annex Tree Map to your website or community page.

Get Embed Code
Locate

Find coordinates

Need latitude and longitude for a tree location?

Find Coordinates
Easy ways to measure a tree's height

You do not need special equipment. These simple methods work for community mapping.

Stand a known distance from the tree, aim your phone at the top, and note the angle.
Tree height ≈ (Distance × tan θ) + Eye height
Example: 10m distance, 40° angle, 1.6m eye height → about 10m tree.

Measure the tree's shadow and your own at the same time.
Tree height = (Tree shadow ÷ Your shadow) × Your height
Works best on a sunny day with clear shadows.

Hold a stick vertically at arm's length and walk until it visually covers the tree. The distance from you to the tree roughly equals the tree's height.

Face away, bend forward, look back between your legs. Walk back until you can just see the treetop — the distance to the trunk is a rough height estimate.
Measuring DBH

DBH = diameter at breast height, measured at 1.3m above the ground.

Measure the trunk at about 1.3m above the ground (roughly 4.5ft), on the uphill side of the tree.

Wrap a tape around the trunk to get circumference, then convert:
Diameter = Circumference ÷ 3.14
Example: 94cm circumference = ~30cm DBH.

Wrap string or a shoelace around the trunk, mark where it meets, then measure the length at home.

On slopes, measure from the uphill side. If there's a branch or bump at breast height, go slightly above or below and add a note. For multi-stem trees, measure each main stem separately.
Common questions

Spotters can submit corrections to existing trees without any account — their suggestions go into a review queue. Mappers have admin access and a GitHub account, so their edits go live immediately and they can also add new trees. Stewards manage the community — they can grant Mapper access to new contributors and review open Spotter suggestions.

You need a GitHub account and write access to the repository. Ask a Steward to add you as a collaborator. Once added, connect your GitHub account through the admin editor to have your commits attributed to you.

It creates a GitHub issue with the suggested change. A Mapper or Steward reviews it, applies it to the data file, and closes the issue. You can track progress in the issue tracker.

The updates page shows recent commits and open community edit requests. The issue tracker lists known problems, missing details, and improvement ideas.

Yes. Use the embed page to generate iframe code. The underlying data is open GeoJSON and can be used with other mapping tools, research projects, or educational purposes.

Yes. You can fork the repository, replace the data with your own, and adapt the project for another neighbourhood, campus, park, or city. Start from the GitHub repo.

Know a school, group, or community that should use this map? Share it or embed it to help grow the project 🌳