MIS314 Utility Tree Work

A Minimum Industry Standard for utility tree work

This book is one in a series of Minimum Industry Standards produced by Arboriculture Australia Ltd and the New Zealand Arboricultural Association in consultation with the national arboriculture community in both countries. These industry peer-reviewed documents provide a ‘body of knowledge’ which is shared by practitioners and can be used as the basis for training, dissemination of skills and professional development.

This document covers the work tasks of utility tree work around conductors and other assets, including a brief summary of the underpinning knowledge necessary to select and perform suitable pruning operations to achieve a variety of objectives.

MIS314 New Zealand Version (for use in New Zealand)

Utility tree work is a broad term which covers a wide range of tasks. In the context of this standard, the term utility tree work is used specifically to describe all tree pruning and removal work in the vicinity of utility infrastructure.

This document is one in a series of Minimum Industry Standards, which are nationally agreed standards developed by tree workers as descriptions of the skills and knowledge that are required to safely perform tree work tasks. This standard focuses on the role of the tree worker, performing vegetation management tasks such as tree pruning or removal.

This standard does not describe scoping, auditing, setting clearance distances, identifying hazard trees, or other tasks which are required by network authorities. Whilst an overview of vegetation management requirements is provided, management-level considerations are beyond the scope of this standard.

This standard describes tree trimming and removal work performed by a vegetation management worker.

Industry partners

The Minimum Industry Standard series was produced by Arboriculture Australia Ltd and the New Zealand Arboricultural Association in partnership with the following state and national industry bodies. The document bears their logos as a mark of ratification.

CONTENTS:

1: Vegetation management and utility tree work

Introduction to vegetation management

• Clearance distances
• Maintenance cycles
• Tree pruning
• Tree removal

Vegetation management: retaining trees

• The vegetation management process

Working near electrical conductors

Approach Distances (MADs and SADs)

Authorised and Competent Persons

Close Working Zones

• Beyond reach and controlled movement
• Reasonable worst-case

Example control measures for work near electrical conductors

Risks of utility tree work

• Emergency preparation and response for the electrica environment
• Fallen or impacted powerlines

Personal Protective Equipment for vegetation management

• Specialist pruning equipment

 

2: Overview of tree health, growth and structure

Tree species

Tree health

Pruning impacts: loss of photosynthetic material

Pruning impacts: physiological impacts

Compartmentalisation and barriers to decay

• Occlusion
• Target pruning

Age and health of tree

• Pruning objectives by age class

Tree structure

Growth habit

Sub-optimal structure

• Branch and stem attachment
• Co-dominant stems
• Crossing or rubbing branches
• Epicormic shoots

 

3: Tree pruning

Planning pruning

• Over-pruning
• Selecting pruning type

Target pruning

Reduction pruning

• Branch reduction cuts
• Examples of incorrect branch reduction cuts
• Stem reduction cuts
• Reduction pruning for clearance

Branch and stem removal

• Branch removal cuts

Directional pruning

• Directional pruning styles
• Establishing crown structure for directional pruning

Compliance pruning

Compliance pruning types

Additional pruning techniques

Deadwood removal

• Retaining deadwood in mature and veteran trees

Formative pruning and structural pruning

Regrowth management

Making pruning cuts

Pruning cut sequence

• Cut sequence and branch behaviour

 

4: Environmental considerations

Biosecurity and transmission of pathogens

• Examples of transmissible tree diseases

Biosecurity measures

• Clean On / Clean Off procedure:
• Kauri dieback

Ecological considerations

Native flora protection

Native fauna

• The tree as a keystone structure
• The ecological value of deadwood
• Retention of habitat