Whether you are the owner of a single tree or manage thousands of trees, we can help. Purearb provides independent arboricultural and environmental consultancy that incorporates a holistic approach to green space management integrating local government and private sector goals. Purearb has developed sound management methodologies in tree maintenance, protection, and replacement within and around the urban environment.

Tree Condition Surveys

A tree condition survey assesses the condition of your tree(s) on site; whether you are a landowner or an agent for multiple sites, we can help!

This comprehensive survey assesses the condition of the tree’s health and structure. It Provides clients with the relevant information to implement future management plans and supports in the decision-making process concerning for example, but not limited to, an ageing tree population. Recommendations can then be made to any remedial pruning work, to limit the risk of any observed potential hazards and to ensure the continued management of the tree(s).


The comprehensive survey is ideal for housing associations, local authorities and other bodies who are publicly accountable, such as Schools, Kindergarten and Retirement Homes.

Tree Hazard Assessments

Tree safety management is a matter of reducing the risk of significant harm from tree failure to an acceptable level while sustaining the benefits conferred by trees. Purearb consultants are trained in the Quantified Tree Risk Assessment (QTRA) system, which applies predetermined limits of sustainable or acceptable risk principles to tree safety management.

Through a tree safety management program, that is annually inspecting your trees and choosing preventive care; you can take active steps towards avoiding damages to persons or property while maximising the many benefits your trees provide.

Tree Reports 

Depending on our clients’ requirements we provide information and data gathered from inspections and assessments through an easy to understand report.


We offer various types of arboricultural reports and surveys. Purearb commonly produces Tree Survey Reports, Detailed Tree Condition Reports, and Arboricultural and Tree Protection Method Statement Reports.

Trees & Development Plan

A tree development plan is frequently required when construction or demolition is likely to come in conflict with trees. This service identifies trees that are likely to be affected by the proposed development, such as the ones to be removed, those to be retained and protected, as well as identifying and considering alternative methods of construction to prevent damage to retained trees. Through this plan, Purearb identifies tree related works essential to ensure ongoing protection during the construction phase of the development.

For this purpose, Purearb uses a mapping and augmentation software that enables us to accurately plot trees and calculate root protection areas. Our onsite flexibility and capabilities allow us to survey and plot large areas prior to construction swiftly and to identify tree conditions and their retention potential, producing appropriate plans for tree protection. All data gathered from this process is compiled into BS5837: 2012 fully compliant itineraries and reports to support the planning process. Expert advice will be given by our qualified staff to ensure tree safety, providing as well a range of solution to facilitate the construction whilst minimising potential harm to retained trees.

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Tree Valuation Reports

A standard method of evaluating trees is essential for those responsible for managing and making the decision about trees, and their preservation, whether in an urban or rural environment.


Our staff are trained in the Standard Tree Evaluation Method (STEM) and International Society of Arboriculture (ISA) valuation method. These systems primarily prescribe a monetary value according to the tree’s amenity value; usually for insurance, compensation and litigation purposes.  The significance of placing a dollar value on trees is that they are then recognised as assets, having major implications, not only in their management, but also in the decision-making processes involving trees.

PiCUS Sonic Tomography

Using ultrasound waves, PiCUS Sonic Tomography assesses the internal structural condition of trees. This system provides an efficient, non-invasive method to evaluate decay patterns and structural integrity of living trees.

This system measures the speed in which wood transmits acoustic waves: sound travels slower through decayed wood or cavities than through solid wood. Internal decay is a major concern, especially with mature trees in proximity to properties and people. Structurally weakened trees are more susceptible to breaking and falling in adverse weather conditions. Test results are shown as a colour coded two-dimensional image, where decay and damaged wood are evidently represented, enabling the client to see the internal structure of trees.

IML Micro-Drill (Resistograph)

The IML-RESI F-Series wood testing system measures internal wood resistance; damaged wood is less resistant in comparison to sound wood. Measurements are typically taken at four points around the tree, and results printed on a wax paper strip. By pairing the Tree Condition Survey with an IML tree inspection tool, our company can interpret the internal health of the subject tree(s). That way we can recommend an appropriate measure early enough to prevent damages to persons or property and to preserve precious tree populations.

In addition, the IML-RESI F-Series coupled with the special adapter enables us to examine utility poles and playground apparatus without excavating around the test location, taking measurements directly from the soil level.

PiCUS Tree Motion Sensor 3


The safety of trees differentiates between two main failures: uprooting and stem fracture.

The Wind-Reaction-Measurement using the PiCUS Tree Motion Sensor 3 measures the natural reaction of the tree, including all factors that influence the wind load (tree properties, exposition, wind speed).

During a measurement, the tree's reaction to naturally occurring wind is measured. The tilt in the root plate occurs when the tree is subjected to a gust of wind. The strength of root-plate inclination is calculated for the tree's anchoring strength and the potential for partial root-plate or catastrophic failure events.  

Significant & Notable Tree Management

The heritage, cultural and environmental value of Significant and Notable trees are generally regarded as those trees or group of trees with special importance. Because they commemorate significant moments in time, or are critical to the survival of other species or are exceptional examples of a species in terms of age, stature, character and visibility that they are regarded as the finest specimens in the district.

Here at Purearb, we pride ourselves in providing a holistic approach to these sensitive trees. We offer a range of management packages which aim to promote and safe guard these green infrastructure assets.

Conservation Area Advice

New Zealand’s native woodlands encapsulate a unique country’s wild coastal regions with glacial valleys, and far-reaching sandy beaches: “Aotearoa, the land of the long white cloud”. Increased pressure on this defining landscape as the demand for commercial and residential development encroaches and alters the landscape – makes these environments more crucial to retain.


Careful management can provide valuable habitats, increase biodiversity, as well as to promote and encourage public awareness. Through management plans that promote natural regeneration, restoration, natural pruning techniques, deadwood management and promoting beneficial fungi, our services aim to assist the land owner in achieving these goals with a carefully tailored management plan.

Arboricultural & Environmental Consultants