Edition: June 2012
Specification: Part M40 Maintenance Pruning
PART M40
MAINTENANCE PRUNING
CONTENTS
1.
2.
3.
4.
General
Clearance Envelope Pruning
Tree Pruning/Removal other than for Routine Maintenance of Clearance Envelopes
Fauna Habitat
1.
GENERAL
This Part specifies the requirements for maintenance pruning activities on DPTI roads.
All pruning, including on-ground support work, shall be carried out by personnel who are trained to the appropriate
level for the type of work being performed, and have a full appreciation of the principles, techniques, hazards and
safety procedures involved.
Where the Contractor, after full inspection of a tree for pruning, considers that the tree is dangerous and requires
removal, the Contractor shall immediately notify the Superintendent.
2.
CLEARANCE ENVELOPE PRUNING
2.1.
General
Clearance envelope pruning is defined as pruning of vegetation within an "envelope" of a height and width as
detailed in the DPTI Vegetation Removal Policy. Maintenance pruning also applies to the control of vegetation at
and around signs and roadside furniture and to provide sight distance.
2.2.
Clearance Envelope Pruning Methods
The Contractor shall examine the site conditions and determine the most suitable method(s) of tree pruning.
(a) Chainsaw/Polesaw
Pruning of secondary branches shall conform to AS 4373, with branches pruned to a major limb or the next
branch junction, which may require pruning beyond the defined clearance envelope.
(b) Side Trimming
Unless otherwise specified, side trimming machines, except flail mowers, are permitted.
The Contractor shall minimise damage to vegetation (including ripping or tearing of limbs) by:
(i) ensuring blades are sharp; and
(ii) driving at a speed that enables branches to be cut cleanly; and
(iii) undertaking follow-up hand pruning (in accordance with AS 4373) on all branches over 100mm
diameter and any torn or ripped branches within 1 week of side trimming.
The Superintendent may require the Contractor to cease work and modify work practices if excessive
ripping or tearing of limbs is observed.
Side trimming machines shall not be used on sections of road identified in the Contract Specific
Requirements and within built up areas.
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2.3.
Specification: Part M40 Maintenance Pruning
Disposal of Cut Material
The Contractor may use an approved motorised chipping unit to process the cut material. The unit shall be in good
working order, shall comply with all applicable OHS&W, noise and spark arrestor requirements, and shall be
operated only by trained operators equipped with appropriate personal safety equipment.
Unless otherwise specified, chipped prunings may be spread evenly over the ground taking care to avoid indigenous
grasses and ground covers. The spread chippings are not to exceed 100 mm in depth across the site.
Chipped prunings may not be spread in Roadside Significant Sites containing high value native vegetation or rare
flora. Roadside Significant Sites relevant to this contract are identified in the Contract Specific Requirements.
Cut vegetation containing seeds of environmental weed species shall not be spread within the road verge. Such
material must be disposed of at a licensed waste facility or burnt.
In High Risk Phytophthora (Dieback) areas, all cut material that has been in contact with soil shall be disposed of at
a licensed waste depot or burnt. High Risk Phytophthora (Dieback) areas are listed in the Contract Specific
Requirements.
3.
TREE PRUNING/REMOVAL OTHER THAN FOR ROUTINE MAINTENANCE OF
CLEARANCE ENVELOPES
3.1.
General
All pruning shall conform to AS 4373 "Pruning of Amenity Trees". Equipment that wounds the bark or conductive
tissues (i.e. spurs, spikes, hooks) shall not be used on sections of the tree to be retained. All cutting tools shall be
sharp and branches shall be undercut to prevent splitting or tearing of the branch collar or trunk.
3.2.
Tree Pruning/Removal Methods
Prior to tree pruning or removal, the Contractor shall assess the site conditions as well as the tree’s health, growth
habit, structure, and stability and pruning requirements. Based on this assessment, the Contractor shall select the
most suitable method of tree pruning/removal from the methods below.
(a) Deadwooding
Deadwood shall be removed from the tree.
(b) Selective Pruning
Branches identified by the Superintendent shall be removed.
(c) Clear Fell
This method shall only be used for tree removal where there is sufficient area in all directions for the tree to
be felled safely, without damage to persons, property and surrounding vegetation.
(d) Use of Climbers
Tree removal or tree pruning shall be carried out by the physical climbing of the tree and the dismantling of
branches (and trunk sections where appropriate) progressively downwards. The Contractor shall ensure
that all climbers and supervising staff meet approved accreditation standards and that all climbing, branch
support and lowering equipment complies to relevant standards, is fit for purpose and in good working
order. The material shall be lowered to the ground by means of ropes, crane etc., unless approval has been
obtained to drop material to the ground (only where there is no risk to persons, property or existing
vegetation).
(e) Elevated Platform
This method shall be used where machinery access is available, with one or two operators in a basket
traveling up in the crown to remove branches. The Contractor shall ensure operating staff have received
approved training in use of this equipment. The material shall be lowered to the ground by means of ropes,
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Specification: Part M40 Maintenance Pruning
crane etc., unless approval has been obtained to drop material to the ground (only where there is no risk to
persons, property or existing vegetation).
3.3.
Disposal of Cut Material
The maintenance operation shall be carried out in a manner involving minimal movements across the site resulting
in minimal disturbance to the vegetation, soil and watercourses.
The Contractor may use an approved motorised chipping unit to process the cut material. The unit shall be in good
working order, shall comply with all applicable OHS&W, noise and spark arrestor requirements, and shall be
operated only by trained operators equipped with appropriate personal safety equipment.
All material generated from pruning and removal activities must be removed from the site, unless prior written
consent from the Superintendent is obtained. All non indigenous plant species shall be disposed of at licensed waste
depot and the contractor shall be responsible for obtaining all necessary permits to undertake this activity. In High
Risk Phytophthora (Dieback) areas, all cut material that has been in contact with soil shall be disposed of at a
licensed waste depot or burnt.
Where approval by the Superintendent is given in writing, the following disposal methods shall be permitted:
(a) Native indigenous chipped prunings may be spread evenly over the ground taking care to avoid indigenous
vegetation including but not limited to grasses and ground covers. The spread chippings are not to exceed
100 mm in depth across the site.
(b) Non indigenous plant species may be left on site where they provide protection to exposed soil, will not
inhibit regeneration of indigenous species, will not significantly increase the current fuel load at the site
and do not contain seed.
(c) Cut material may be burnt on site or at a suitable location proposed by the Contractor and approved by the
Superintendent. The Contractor shall comply with all fire bans and restrictions, and shall obtain an
appropriate permit to carry out burning.
4.
FAUNA HABITAT
The removal of trees, particularly in rural and remote areas, often results in the removal of hollows. These hollows
have important habitat values for indigenous fauna species. Where hollows are encountered during the tree removal
process, the Superintendent shall be contacted to arrange suitable relocation.
Every effort shall be made to avoid the disturbance of native fauna occupying tree hollows. In the event of the
discovery of occupied nests or hollows, or injured fauna, the Superintendent shall be immediately notified.
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