This unit of competency describes the skills and knowledge required to decide on the appropriateness for retaining trees and to assess, plan and monitor the protection of trees on construction and development sites where trees subject to retention are exposed to potential damage.

The unit applies to individuals who work in arboriculture and analyse information and exercise judgement to complete a range of advanced skilled activities and demonstrate deep knowledge in a specific technical area. They have accountability for the work of others and analyse, design and communicate solutions to a range of complex problems.

Legislation, regulations and by-laws relating to the treatment and removal of trees apply in some states and territories.

An individual demonstrating competency must satisfy all of the elements and performance criteria in this unit.

There must be evidence that the individual has on at least one occasion developed an arboricultural impact assessment report for a development site and has:

identified and researched the impact and specific requirements of legislation, Australian Standards, and local government laws for trees on development site

conducted site assessment and identified conditions that impact tree protection program

identified work health and safety hazards, assessed risk and applied controls for site

identified hazards and assessed the risks that harm trees

located, confirmed and plotted all trees on survey plan

collected plans and documentation

identified and recorded tree by botanical and common name and included a record of:

tree height, crown spread and diameter-at-breast-height (DBH), diameter at ground level and statutory dimensions

age class and estimated life expectancy

tree health in relation to tree physiology and pathology

condition of tree structure in relation to tree anatomy

assessed the following values for trees:

heritage and cultural

habitat, ecological and environmental

location of tree to existing and past site structures

determined the tree retention value

compiled tree assessment data for report

recorded all trees suitable for retention

determined and plotted indicative tree protection zone (TPZ), tree identifiers for each tree on survey plan

documented preliminary arboricultural report

interpreted plans, designs, working drawings, terms, symbols and language for development

assessed and determined controls for mechanical and chemical damage affecting trees

provided client with preliminary feedback for potential improvements

liaised with client on design development and assessed impact of construction on trees

liaised with design team to develop tree sensitive design and construction methods

assessed development requirements for site access and logistics

reviewed indicative tree protection zone and determined:

extent of encroachment into indicative TPZ

impact of works on structural root zone (SRZ)

determined extent of SRZ

determined and recorded level of encroachment and actual TPZ for trees to be retained

assessed the following factors affecting tree viability for a major encroachment:

location and distribution of roots

potential loss of root mass

species tolerance to root loss

age, health, size, lean and stability of tree

assessed impact of encroachment on health, physiology and structural integrity of tree

assessed impact on soil characteristics and volume from past, existing or planned structures

considered site and design factors to minimise impact of proposed encroachment

rationalised all factors to decide on the viability of the tree

determined remedial measures to protect the tree

investigated, specified and produced installation and construction drawings for tree protection devices and systems to mitigate tree damage

provided advice to client on tree removal and tree pruning program

prepared a draft arboricultural impact assessment report

developed a tree protection plan and drawings

prepared, documented tree management and monitoring, including strategies to handle problems

consolidated reports, plans and guidelines into final arboricultural impact assessment report in both:

digital format

print format

presented report to client.

An individual must be able to demonstrate the knowledge required to perform the tasks outlined in the elements and performance criteria of this unit. This includes knowledge of:

legislative and regulatory framework for trees on development sites, including:

role of Australian Standards AS2303, AS2223, AS3743, AS4970 and AS4373

specific requirements of statutory authorities

local government tree protection and preservation regulations

construction drawings, plans and documentation, including:

types of drawings and plans

terms, symbols and language used in development

version control of drawings, including revision and issue dates

working and communicating with clients and development design personnel

conducting site assessment and conditions that impact tree protection programs, including:

development site safety and safe access procedures

plotting trees/tree identifiers onto survey plans

naming and recording tree by botanical and common name

methods for determining tree dimensions, height, crown spread and DBH

age class and estimated life expectancy

tree health in relation to tree physiology and pathology

assessing and determining the viability of a trees

soil volume and characteristics on development sites

tree values and importance, including:

heritage and cultural values

habitat, ecological value

environmental values

methods of determining retention value

the principles of TPZ, including:

methods of mechanical and chemical damage to trees on development sites

impact of proposed development on trees

SRZ

levels of tolerance to encroachment and potential loss of root mass

species tolerance to root loss

type and structure of tree impact assessment reports, including:

purpose and structure of preliminary arboricultural report

purpose and structure of arboricultural assessment report

use and interpretation of development plans and documentation

drawing techniques for illustration in reports and plans, including digital images

tree protection plans and drawings

purpose and structure of tree management and monitoring guidelines

presenting reports in digital or paper-based formats

tree protection devices, methods and systems, including:

designs and their purpose

tree response to tree protection systems

installation and construction methods for tree protection.

Assessment of the skills in this unit of competency must take place under the following conditions:

physical conditions:

a development worksite with existing trees, or an environment that accurately represents workplace conditions

resources, equipment and materials:

computer with word processing and drawing software

digital image capture device

personal protective equipment

basic diagnostic tools, including sounding hammer, trowel, probe, cordless drill

basic soil testing equipment

trees

specifications:

client brief and instruction for safety audit objectives

industry standards AS2303, AS2223, AS3743, AS4970 and AS4373

relationships:

client.

Assessors of this unit must satisfy the requirements for assessors in applicable vocational education and training legislation, frameworks and/or standards. In particular, assessors must have:

arboriculture vocational competencies at least to the level being assessed

current arboriculture industry skills directly relevant to the unit of competency being assessed.

This section describes those language, literacy, numeracy and employment skills that are essential for performance in this unit of competency but are not explicit in the performance criteria.

Arboriculture (ARB)