An arborist report is the document a consulting arborist hands a client after looking at their trees: a homeowner worried about a big oak, a city deciding what to do with a street tree, a developer who needs to know which trees can stay, or an attorney who needs an independent opinion. It says what you were asked to do, what you looked at and how, what you found, what you think it means and what you recommend. This template walks that order, with a list for every tree, so the report is half-written by the time you leave the site. Fill it in here and download a PDF without an account, or speak while you walk, and the document writes itself.
Start with the assignment, not the trees
The first page of a good report answers three questions before it mentions a single tree: who asked, what they asked for, and what the report is for. A pre-purchase look at a yard and an expert opinion for a boundary dispute call for very different depth, and a reader who knows the purpose can judge whether the report did its job.
The scope also protects you. If you were asked about four trees in the front yard, say so, and say that the rest of the property was not part of the work.
Limitations belong near the top
Every inspection has edges. Ivy hid the lower trunk, the neighbor's side was off limits, nobody climbed the tree, the root zone was under a driveway, or it was February and the crown had no leaves. Listing these early tells the reader how much weight to put on each conclusion, and it is far more useful than a paragraph of general disclaimers at the back.
One entry per tree, then the thinking
Each tree gets the same short block: a tag or an unmistakable description, common and botanical names, trunk diameter at 4.5 ft, height and spread, where it stands, an overall condition and what you actually saw, with a photo. Keep observations factual in the list — "included bark at the main union, 18 in long crack on the north side" — and save the interpretation for the discussion section.
The discussion is where you connect what you saw to the client's question: why that crack matters for a tree leaning over a bedroom, or why a declining ash is not worth treating. Conclusions then state the answer in a few plain sentences.
Recommendations someone can act on
Each recommendation names the trees, the action, a priority and a time frame. "Reduce the north limb of T-3 by about 10 ft to a lateral, within 30 days" can be priced and scheduled; "consider pruning" cannot. Many arborists write pruning work in the language of ANSI A300 so that a crew and a client read it the same way.
An urgent recommendation shows up in the report's summary of findings, so the most important thing you found is the first thing the client sees.
Common questions
What should an arborist report include?
The client, the site and the date; the assignment and purpose; the methods used and the limits of the inspection; a description of the site and its targets; each tree with ID, species, size, condition and observations; a discussion; conclusions; recommendations with priority and timing; the assumptions and limiting conditions; and the arborist's name, credentials and signature.
Who can write an arborist report?
Anyone can write one, but the people who read them — cities, courts, insurers, lenders — usually expect a credentialed arborist, such as an ISA Certified Arborist or a member of ASCA, and some cities require a particular credential for permit work. The form records the credentials you type; it does not verify them.
Is this the same as a tree risk assessment?
No. A tree risk assessment answers one question about one tree or a group of trees: how likely is it to fail and hit something, and how bad would that be. An arborist report can include a risk opinion, but it usually covers more — health, value, construction impact, whether to keep or remove — and it is written for a particular client and purpose.
What are assumptions and limiting conditions?
They are the plain statements an opinion rests on: that the information you were given about the property is accurate, that you looked only at the trees named and only from where you could reach, that trees are living things and can fail without warning signs, and that the report is valid for the conditions on the visit date. Write them in your own words and keep them short.
How long is an arborist report valid?
Trees change and so do sites, so most arborists say a report describes conditions on the day of the visit. Many clients and cities treat a report as current for about a year, or until a storm, construction or a visible change in the tree; if it matters, state your own view in the limiting conditions.