An arboricultural report is any professional report about the trees on a site — in UK planning it usually means one or more of the six BS5837 documents, of which the tree survey report is the foundation the rest are built on. People use "arboricultural report", "tree survey report" and "BS5837 report" loosely and often interchangeably, which is exactly why applications go wrong: an applicant orders one document when the council's checklist wanted another, and finds out at validation.
The "report" is really a family of documents
There is no single thing called the arboricultural report. A full BS5837 package builds up in stages, and each element is a distinct deliverable produced at a different point in the planning journey. When a validation list or a planning condition says "arboricultural report", your first job is to work out which of these it actually means.
| Document | What it is | Typical stage |
|---|---|---|
| Tree Survey (with schedule) | The base record: every relevant tree's species, size, condition, category and root protection area, presented as a table | Pre-design / with the application |
| Tree Constraints Plan (TCP) | A scaled drawing overlaying the survey data — positions, crown spreads and RPA circles — showing what the trees "cost" the developable area | Pre-design / with the application |
| Arboricultural Impact Assessment (AIA) | Assesses the proposed layout against the trees: what's removed, what's retained, what conflicts arise | With the application |
| Tree Protection Plan (TPP) | A drawing showing barrier fencing, exclusion zones and ground protection for retained trees | With the application and/or to discharge a condition |
| Arboricultural Method Statement (AMS) | The "how": detailed methodology for any works within or near RPAs | Often a pre-commencement condition |
| Site Supervision / Monitoring | On-site oversight during construction, with visit records and certificates | During construction, post-permission |
The mental model that saves the most grief: the survey, TCP and AIA are the pre-permission "can we build this?" documents; the TPP, AMS and supervision are the post-permission "prove you'll protect them" documents, discharged as conditions after you already hold consent.
The tree survey report, anatomy of
The tree survey report is where every other document starts, so it is worth knowing how to read one. It has two parts that must agree with each other: a schedule (the table) and a plan (the drawing), tied together by a reference number on every tree. If the schedule says T1 is a mature oak and the plan puts T1 on a sycamore, the report is worthless — that cross-referencing is the first thing a good tree officer checks.
The schedule — an annotated example row
Here is a single row from a typical BS5837 tree survey schedule, decoded column by column:
| Ref | Species | Height (m) | Stem dia. (mm) | Crown N/E/S/W (m) | Age class | Condition | Remaining years | Category | RPA radius (m) |
|---|---|---|---|---|---|---|---|---|---|
| T1 | Oak (Quercus robur) | 18 | 620 | 6/7/6/5 | Mature | Good | 40+ | A1 | 7.4 |
- T1 — the tree reference. This same tag appears on the plan, so anyone can find the physical tree.
- Oak (Quercus robur) — common and botanical species name.
- 18 — height in metres.
- 620 — stem diameter in millimetres, measured at 1.5 m above ground (diameter at breast height, DBH). Multi-stem trees get a combined notional diameter.
- 6/7/6/5 — crown spread in metres to the four cardinal points (N/E/S/W), so the canopy can be plotted accurately.
- Mature — age class (young, semi-mature, early-mature, mature, over-mature, veteran).
- Good — physiological and structural condition.
- 40+ — estimated remaining contribution in years.
- A1 — the BS5837 retention category. Category A = high quality (40+ years' safe useful life); the 1 subcategory means its value is mainly arboricultural.
- 7.4 — the root protection area radius in metres. Here 12 × 0.62 m stem diameter ≈ 7.4 m, the notional rooting circle that must be safeguarded.
Read a whole schedule and you can see at a glance which trees the design should bend around (the As and Bs) and which are constraints of little weight (the Cs and Us).
The categories, in detail
Every tree is graded into one retention category, with a subcategory denoting why it has value. This grading is the single most consequential judgement in the whole report, because it drives which trees the planning balance protects.
| Category | Meaning | Est. remaining contribution | Plan colour (convention) |
|---|---|---|---|
| U | Unsuitable for retention — dead, dying, dangerous or so defective it can't reasonably be kept | Under ~10 years / removal | Dark red |
| A | High quality — good examples worth retaining | 40+ years | Green |
| B | Moderate quality — retention desirable; may have remediable defects | 20+ years | Blue |
| C | Low quality — unremarkable, or young/small; little constraint | 10+ years (or young stems under 150 mm) | Grey |
The subcategory shows the type of value: 1 = mainly arboricultural qualities, 2 = mainly landscape qualities, 3 = mainly cultural or conservation value. So "A1" is a high-quality tree valued arboriculturally; "B2" a moderate tree valued for its landscape contribution.
Note: BS5837:2012 uses U for unsuitable trees. Some older references and third-party guides mention a "Category R" (remove) — that code is from the superseded 2005 edition and is no longer part of the standard. If a report you are handed says "Category R", it is either out of date or wasn't written to the current standard.
Two words that carry all the legal weight
A recurring source of confusion is worth stating plainly: BS5837:2012 is a British Standard, which means it is guidance, not law. Its full title ends in the word "Recommendations", and it uses "should", not "must". An arboricultural report written to BS5837 is not itself legally required by the standard.
The compulsion to produce one comes from three separate places, and a good report keeps them distinct:
- Local validation — your council won't register the application without the arboricultural documents its checklist demands.
- Planning conditions — permission is granted subject to further tree detail, such as an AMS, discharged before works start.
- Statutory tree protection — Tree Preservation Orders and conservation-area rules, which are genuine criminal law and sit entirely outside the planning application.
Getting these confused is how homeowners end up prosecuted for felling a protected tree they assumed their planning permission covered — it usually doesn't.
Who should write it — and why it matters
There is no legal licence to be an arboriculturist and no statutory register you must appear on. BS5837 simply asks for someone "suitably qualified and experienced" — in practice, a degree or Level 5+ qualification in arboriculture plus around three years' relevant recent experience. Councils give the most weight to reports from an Arboricultural Association Registered Consultant (AARC) or an Institute of Chartered Foresters (ICF) chartered arboriculturist. Anyone can call themselves an "arborist"; those accreditations, plus professional indemnity insurance, are what make a tree officer trust the report without a fight. A thin report from an unaccredited author that gets rejected is a false economy. See find a tree surveyor for what to check.
Which report do you actually need?
- Trees on or near the site, planning application coming up? You'll need at least a tree survey, and almost certainly an AIA. Start with do I need a tree survey for planning.
- Permission already granted with a tree condition? You need an arboricultural method statement to discharge it before you start.
- Buying a house near a large tree? That is a different, subsidence-focused report — see tree survey for a mortgage.
- Worried about a tree's safety? That is a tree risk assessment, not a BS5837 survey.
- Budgeting? See what each report costs on our tree survey cost page.
Requirements — and validity — are set locally
Which arboricultural documents you must submit, how they are worded, and how recent the survey has to be are all decided by your individual local planning authority, not by any single national rule. There is a national baseline for what makes an application valid, but the arboricultural specifics are a local overlay: the trigger wording, whether a full AIA is wanted upfront or conditioned later, local TPO density and conservation-area coverage, and how strictly the tree officer reads a report all vary from council to council.
Validity is the same story. There is no statutory expiry, but many authorities expect a survey done within the last 12–24 months and will ask for an update if it is older or if a season with storms or disease may have changed the trees. That window is a local expectation, not a fixed rule — so check yours.
Requirements differ noticeably between, for example, Leeds, Bristol and a conservation-heavy borough like Lambeth. Before you commission anything, read your authority's validation checklist, and run a TPO check on the trees involved — a protected tree changes everything. PlanWatch tracks live tree-related planning activity per council, so you can see what is being submitted, conditioned and refused near you before you spend a penny — start from the tree-surveys hub.
Scotland, Wales and Northern Ireland
BS5837:2012 applies UK-wide as a British Standard, so an arboricultural report looks the same wherever it is written. The statutory framework it plugs into differs by nation: Scotland works under the Town and Country Planning (Scotland) Act 1997, and Wales and Northern Ireland have their own parallel regimes for validation and tree protection. The documents are the same; the process and protection detail around them are not — always confirm with the specific local authority before you rely on any report.