What Is a BS5837 Tree Survey? (And When Do You Need One?)

Written By Wez - 04/08/2026

What the survey actually contains

A BS5837 survey records every relevant tree (on the site and within influencing distance of it, including neighbours’ trees) and for each one documents species, height, stem diameter, crown spread, age class, physiological and structural condition, and estimated remaining life. Each tree is then graded into categories:

Category A: high quality, significant trees that should strongly constrain the design
Category B: moderate quality, worth retaining where possible
Category C: low quality, limited constraint
Category U: trees whose condition means they can't realistically be retained

Crucially, the survey also calculates each tree’s Root Protection Area (RPA), the zone around the stem where roots must be protected from excavation, compaction, and level changes. RPAs, not crowns, are what actually shape site layouts: a tree’s roots typically matter further out than its branches.

The document family
(and what councils ask for)

Tree Survey + Tree Constraints Plan: the baseline facts: what’s there, what grade, where the RPAs fall. Done before design, ideally

Arboricultural Impact Assessment (AIA): takes the proposed design and assesses what it does to the trees: removals, RPA incursions, shading and future-pressure issues

Arboricultural Method Statement (AMS) + Tree Protection Plan (TPP): the how: fencing locations, ground protection, no-dig construction specifications, and the sequencing that keeps retained trees alive through the build

Smaller householder applications (an extension near one protected tree) may only need a proportionate version; larger schemes will need the lot, and often arboricultural supervision during construction too.

When you need one

A planning application where trees stand on or adjacent to the site (most councils' validation checklists require it explicitly)
Demolition or construction near protected trees or conservation-area trees
Pre-purchase due diligence on a development plot, because tree constraints can take a chunk out of a site's developable area, and finding that out after you've bought is the expensive order of operations

That last one deserves emphasis: a Category A tree with a large RPA in the middle of your proposed footprint is a design problem, a cost problem, and sometimes a viability problem. Survey before you buy, or at least before you design.

Who can do a BS5837 survey?

A qualified arboricultural consultant: councils expect surveys from someone with recognised arboricultural qualifications and experience, and a report that follows the standard’s methodology properly. A landscaper’s sketch or a tree surgeon’s informal opinion won’t validate an application.

What does it cost?

Typically from a few hundred pounds for a small householder site with a handful of trees, rising with tree numbers, site size, and the document stages required; AIA, AMS, and supervision are usually priced as the scheme firms up. Set against planning delays from an invalidated application, it’s cheap insurance.

Where Silver Tree Services fits

We work both sides of this process across Gloucestershire. Our tree survey team provides condition and safety surveys for landowners and managers, and for development projects we’ll advise where your scheme sits, scope what the council is likely to require, and either provide or arrange the right level of BS5837 reporting for the job. Downstream, our teams deliver what the reports require: section felling and pruning of approved removals, site clearance, tree protection fencing, and the replacement planting that planning conditions attach, supplied from our own nursery.

Got a site with trees and a planning ambition? Call 01242 472560 and we’ll tell you what the council will ask for before the council asks.

Related: Tree surveys & reports · TPOs explained · Site clearance

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