Consultancy Services


Arbor Guy uses the Quantified Tree Risk Assessment (QTRA) system to quantify tree risk and develop ‘Risk Index’ codes for individual trees. The Quantified Tree Risk Assessment system applies established and accepted risk management principles to tree safety management.


Arbor Guy can perform an assessment and tree survey of the area proposed for development.  This can include an assessment of tree health and condition to allow decisions to be made on tree retention and removal, also recommendations on suitable plantings for new developments.  Arbor Guy is capable of conducting development works from the planning stage, through construction and to the final hand-over stage.

We can work in with your engineers, landscape designers and architects to identify retention trees, to protect these trees through the development phase and to create landscapes suitable for tree growth. We can advise on the construction of root pathways beneath paved surfaces to ensure that your valuable landscape trees thrive and to minimise future disruption to underground services from root growth. This reduces the time it takes to get that ‘established’ feel in a new development therefore adding value to the property.

We are committed to conducting all our operations with regard to the relevant Australian Standards.

Where there are trees and green spaces, businesses flourish, people linger and property values increase. The physical effects of trees – the shade, humidity control, wind control, erosion control, evaporative cooling, sound and visual screening, traffic control, pollution absorption and precipitation – all have economic benefits.


Arbor Guy has suitably qualified and experienced Cert II, III and Diploma in Arboriculture qualified Arborists that can map, gather relevant data and assess thousands of trees over large areas. Our Arborists can conduct VTA [Visual Tree Assessments], QTRA [Quantified Tree Risk Assessments], VRM [Visitor Risk Management] and generate accurate maps and databases using GIS [Geographic Information System] and GPS [Global Positioning System]. Arbor Guy's systems are compatible with commercial programs such as Autocad, MapInfo, Geobasemap, ESRI Arcview/Arcpad and Pathfinder.


The success of a tree is fundamentally linked to the soil in which it grows. Healthy soils are essential for root development and nutrient uptake. We provide diagnostic services to analyse soil and foliar samples for Ph levels, nutrient content and to test for the presence of toxins. 


Arbor Guy offers a tree mapping and assessment service, which involves GPS location mapping of trees and the gathering of tree condition data. This data is collected using hand-held GIS devices and collated into a database report. We can generate high quality maps to pinpoint tree locations and overlay information onto aerial imagery.

The following list of tree attribute data is typical of a basic tree survey although attribute fields can be tailored to the individual client requirements:

  • Tree species (genus/species)
  • Height
  • Diameter at breast height (DBH)
  • Health (good/fair/poor)
  • Structure (good/fair/poor)
  • Quantified Tree Risk Assessment ‘Risk Index’
  • Recommended works

i-Tree Eco

i-Tree Eco is a software package first developed by the United States Forest Service and recently adapted for Australian use. The software requires the collection of specific data fields that once analysed provide detailed information to quantify an urban forests structure, environmental effects, energy reduction and values to the community.

i-Tree Eco can calculate the following parameters based on local measurements:

  • Urban forest structure, including species composition, tree cover, tree density, tree health, leaf area and leaf biomass.
  • Hourly pollution removal by the urban forest for ozone, sulfur dioxide, nitrogen dioxide, carbon monoxide, and particulate matter(PM10).
  • Effects of trees on building energy use (in KWh and dollars saved).
  • Total carbon stored and net carbon sequestered annually.
  • Rainfall interception in cubic meters and the value in dollars saved.

By placing a dollar value on the benefits of the urban forest, the importance of this resource can be made tangible to policy makers, communities and businesses. Arbor Guy can conduct an i-Tree analysis of your trees – from a single plot to an entire city.