A tree survey is a formal, systematic assessment of trees on a specific site, providing a clear inventory of the local tree population. This process is carried out by a qualified arboricultural consultant or arborist who possesses specialized knowledge of tree biology and structural mechanics. The goal of the survey is to collect detailed information about each tree’s species, size, health, and precise location relative to property boundaries or proposed development footprints. The resulting report informs property owners, developers, and local authorities about the condition of the trees and any constraints they may impose on future land use.
The Necessity of Professional Tree Surveys
A professional tree survey is necessary where the presence and condition of trees affect safety, legal compliance, or property development. Surveys are commonly required for local authority planning applications before any new construction, demolition, or significant extension projects begin. Planning departments mandate these surveys to ensure trees are not unnecessarily damaged or removed, especially when they represent a significant landscape feature or habitat.
Property owners also commission surveys as a part of risk management, particularly for trees near buildings, public walkways, or areas of high traffic. An arborist assesses the structural integrity of trees to identify potential hazards like significant decay, structural defects, or instability that could lead to failure in high winds. Identifying these “hazard trees” allows for proactive maintenance, monitoring, or removal, mitigating the risk of property damage or injury.
Compliance with specific legal protections frequently necessitates a survey. Trees protected by Tree Preservation Orders (TPOs) or those located within a Conservation Area cannot be pruned, felled, or otherwise altered without prior written consent from the local planning authority. A survey provides the necessary evidence and justification for any proposed work on these protected specimens. Pre-purchase property assessments often include a tree survey to identify any existing risks, potential liabilities, or future maintenance costs associated with the trees on or near the land.
On-Site Data Collection and Assessment
The survey process begins with the arborist performing fieldwork to gather specific data about every tree on the site. Each tree is assigned a unique identifier, usually a physical tag or number, which links the living specimen to the corresponding data record in the final report. This tagging ensures the accuracy of the inventory and allows for clear communication regarding specific trees.
Once identified, the arborist records various physical measurements, including the tree’s overall height and the spread of its crown. A measurement of the trunk’s Diameter at Breast Height (DBH) is taken at 1.5 meters above ground level, providing a standard metric for tree size and growth rate. These measurements determine the physical space the tree occupies and its potential impact on its surroundings.
A Visual Tree Assessment (VTA) is then conducted to evaluate the tree’s health and structural condition. The arborist looks for external signs of disease, such as fungal brackets or pest infestations, and assesses the tree’s overall vigor. Structural defects, including split limbs, co-dominant stems, or basal decay, are also recorded to determine the tree’s likelihood of failure.
Based on the health, species, life expectancy, and aesthetic contribution, each tree is assigned a retention category, ranging from high-value specimens to those recommended for removal. This categorization guides subsequent planning decisions by highlighting the trees that should be prioritized for preservation during any construction or development.
Interpreting the Survey Report and Recommendations
The final deliverable is a comprehensive document that translates the on-site observations into actionable plans for the client and the planning authority. A central component of the report is the Survey Plan, which is a topographical map showing the precise location of every tagged tree. The plan visually represents the full extent of the tree canopy spread and, crucially, the calculated Root Protection Area (RPA).
The RPA is a defined zone around the tree trunk that must remain undisturbed to ensure the tree’s survival. Alongside the map is the Data Schedule, a tabulated list that corresponds to each unique tree tag, detailing the species, dimensions, condition, and the assigned retention category.
The arborist’s Recommendations section outlines the suggested management actions, which may include specific pruning to remove dead or weak wood, installing support systems like bracing, or recommending removal for safety or poor health. These recommendations are designed to improve the tree’s long-term health and stability, or to mitigate foreseeable risks.
For development projects, the report is prepared in accordance with the British Standard 5837 (BS5837), which provides a standardized framework for managing trees near construction sites. The BS5837 standard requires the preparation of a Tree Protection Plan (TPP) and an Arboricultural Method Statement (AMS). The TPP shows the exact placement of protective fencing around the RPA, while the AMS details the specific measures to be taken during construction, such as ground protection and specialized excavation techniques.