Contact Us

Email us! - General Enquiries, membership, feedback or advertisting.


#1 Code Of Practice – Tree Pruning

The intention of this Standard is to encourage pruning practices and procedures that reduce the risk of hazard development, branch failure, pathogen infection and premature tree death.

Trees often require pruning to maintain clearance for utility services and buildings or to improve the safety, structure, and health of the tree. They are also often pruned to improve the amenity of sites in order to enable successful cohabitation between trees and people.

The procedures in this Standard are guided by theories of branch attachment and compartmentalization of decay in trees. Lopping, topping and flush cutting are unacceptable practices.

Assessment of trees and specification of their pruning should be carried out by a suitably qualified arborist. Pruning should be carried out by arborists or tree workers who are familiar with the principles, techniques and hazards of this work.


1    SCOPE

This Standard specifies methods for pruning of trees and gives guidance on correct and uniform practices. It is intended for use on amenity trees, including palms, and includes removal of deadwood, crown lifting, formative pruning, reduction pruning (including line clearance), selective pruning, crown thinning and remedial or restorative pruning.


2    APPLICATION


This Standard shall apply to any person or entity engage in the business of tree care and maintenance. The Standard will also serve as a guide for property owners and others who specify pruning procedures.


3    REASONS FOR PRUNING

  1. Reduce risk of failure
  2. Provide clearance
  3. Reduce shade and wind resistance
  4. Maintain health
  5. Influence flower or fruit production
  6. Improve a view
  7. Improve aesthetics



4    SAFETY

4.1    Tree maintenance shall be performed only by arborists who, through related training or on-the-job experience, or both, are familiar with the practices and hazards of arboriculture and the equipment used in such operations.

4.2    This standard shall not take precedence over arboricultural safe work practices.

4.3    All operations shall comply with applicable Workplace Safety and Health Act.


5. DEFINITIONS

5.1    Amenity trees
Trees with recreational, functional, environmental, ecological, social, health or aesthetic value rather than for production purposes.

5.2    Anvil-type pruning tool
A pruning tool that has a sharp straight blade that cuts against a flat metal cutting surface, in contrast to a hook-and-blade type pruning tool

5.3    Arboriculture
The art, science, technology, and business of commercial, public, and utility tree care.

5.4    Arborist
An individual engaged in the profession of arboriculture who, through experience, education, and related training, possesses the competence to provide for or supervise the management of trees.

5.5    Bark
All tissues outside the vascular cambium.

5.6    Branch
A lateral shoot on a main axis such as a trunk or another branch. A branch arising off a trunk is a first order branch. A branch arising off a first order branch is a second order branch and so on. Second and successive orders of branches may be referred to as lateral branches.

5.7    Branch bark ridge [BBR]
Raised or furrowed bark in the branch union that marks where the branch wood and trunk wood overlap.

5.8    Branch collar
Overlapping trunk and branch tissue forming a swelling around the base of many branches and containing defensive chemicals.

5.9    Bud
Embryonic vegetative or reproductive tissue, which may be terminal, axillary or adventitious in origin. Buds can be active or dormant.

5.10    Cambium
The dividing layer of cells that forms sapwood (xylem) to the inside and inner bark (phloem) to the outside.

5.11    Cleaning
Selective pruning to remove one or more of the following parts: dead, diseased, and/or broken branches

5.12    Closure
The process of woundwood covering a cut or other tree injury.

5.13    Codominant stems
Stems or trunks of about the same size originating from the same position from the main stem.

5.14    Compartmentalization
Dynamic tree defence process involving protection features that resist the spread of pathogens and decay causing organisms.

5.15    Coppicing
The cutting of a trunk close to ground level in order to stimulate the production of epicormic shoots.

5.16    Crown
Portion of the tree consisting of branches and leaves and any part of the trunk from which branches arise.

5.17    Crown cleaning
The selective removal of dead, dying, diseased, and broken branches from the tree crown.

5.18    Crown lifting or raising
The selective removal of lower limbs from a tree crown to provide vertical clearance.

5.19    Crown reduction
Method of reducing the height and/or spread of a tree crown by making appropriate pruning cuts.

5.20    Crown restoration
Selective pruning to restore the natural growth habit of a tree or to improve the structure, form, and appearance of trees that have been severely topped, headed, vandalized, or damaged.

5.21    Crown thinning
The selective pruning to reduce the density of live branches and does not alter the overall size of the tree.

5.22    Deadwooding
The removal of dead branches.

5.23    Decay
The process of degradation of woody tissues by micro-organisms.

5.24    Epicormic bud
Latent or adventitious bud located at the cambium and concealed by the bark.

5.25    Epicormic shoot
Shoot that arises from latent or adventitious buds that occur on stems and branches and on suckers produced from the base of trees.

5.26    Espalier
The training and pruning of trees against a wall or on a trellis.

5.27    Extruded bark
Outwardly formed bark at the junction of branches or codominant stems.

5.28    Final cut
This is the final cut in the process of the reduction or removal of branches and stems. The purpose of this final cut is to reduce the risk of micro-organism infection according to the principles of branch attachment and compartmentalization to encourage even wound closure (occlusion).

5.29    Flush cut
A cut that damages or removes the branch collar or removes branch and stem tissue and is inconsistent with branch attachment as indicated by the branch bark ridge.

5.30    Formative pruning
The pruning of young and establishing trees with the general aims of directing plant growth and/or developing a sound structure.

5.31    Frond
A leaf of a palm.

5.32    Hanging branches
Unattached, cut or broken branches that are caught in the canopy.

5.33    Heading
1. Cutting a currently growing, or a 1-year-old shoot, back to a bud.
2. Cutting an older branch or stem back to a stub in order to meet a defined structural objective.
3. Cutting an older branch or stem back to a lateral branch not large enough to assume apical dominance in order to meet a defined structural objective. Heading may or may not be an acceptable

5.34    Hook-and-blade-type pruning tool
A pruning tool that has a sharp curved blade that overlaps a supporting hook; in contrast to an anvil-type pruning tool (syn.: by-pass pruner)

5.35    Internodal cut
A cut located between lateral branches or buds.

5.36    Included bark
Inwardly turned bark within the junction of branches or codominant stems.

5.37    Lateral branch
A shoot or stem growing from a parent branch or stem.

5.38    Leader
A dominant or co-dominant, upright stem

5.39    Lions tailing
The practice of removing branches from the interior of the canopy leaving most of the foliage on the ends of branches. This is not crown thinning and may lead to structural hazards.

5.40    Live crown ratio
Ratio of the height of the crown containing live foliage to the overall height of the tree.

5.41    Lopping
The practice of cutting branches or stems between branch unions or internodes.

5.42    Natural target pruning
The removal of branches, stems and stubs such that final cuts are achieved, according to principles of branch attachment and compartmentalization.

5.43    Parent branch or stem
A tree trunk, limb, stem or prominent branch from which, shoots or laterals grow.

5.44    Pathogen
A disease-causing organism.

5.45    Pollarding
Specialty pruning technique in which a tree with a large-maturing form is kept relatively short. Starting on a young tree, internodal cuts are made at a chosen height, resulting in the development of callus knobs at the cut height. Requires regular (usually annual) removal of the sprouts arising from the cuts.

5.46    Pre-cutting
The practice of making an undercut, side cuts and/or scarf cuts that reduce the risk of a branch splitting or tearing. These cuts are made beyond the branch collar and precede the final cut.

5.47    Pruning
The selective and systematic removal of plant parts to meet specific goals and objectives.

5.48    Reduction pruning
The removal of the ends of branches to lower internal lateral branches or stems in order to reduce the height and/or spread of the tree.

5.49    Remedial (restorative) pruning
The removal of damaged, diseased or lopped branches back to undamaged tissue in order to induce the production of shoots from latent or adventitious buds, from which a new crown will be established.

5.50    Selective pruning
The removal of identified or specified branches.

5.51    Stem
Organ which supports branches, leaves, flowers and fruit; may also be referred to as the trunk.

5.52    Stem bark ridge
The ridge of bark that forms in the union between codominant stems.

5.53    Stub
An undesirable short length of a branch remaining after a break or incorrect pruning cut is made.

5.54    Subordinate
Pruning to reduce the size and ensuing growth of a branch in relation to other branches or leaders.

5.55    Topiary
The practice of training and shearing plants into various shapes.

5.56    Topping
The reduction of a tree's size using heading cuts that shorten limbs or branches back to a predetermined crown limit. Topping is not an acceptable pruning practice.

5.57    Tree
Long lived woody perennial plant greater than (or usually greater than) 3 m in height with one or relatively few main stems or trunks.

5.58    Trunk
The main stem.

5.59    Vista pruning
Selective pruning to allow a specific view.

5.60    Watersprouts
Upright, epicormic shoot arising from the trunk or branches of a plant above the root graft or soil line.

5.61    Wound
An opening that is created when the bark is penetrated, cut, removed or injured.

5.62    Woundwood
Partially differentiated tissue responsible for closing wounds. Woundwood develops from callus associated with wounds.


6    TREE INSPECTION

6.1    An arborist shall visually inspect each tree before beginning work. The inspection should include an assessment of the trees health, species, age, condition, growth habit, structure, stability, hazards and growing environment. The distribution of the foliage and wound size should be considered. The need for pruning should be determined. The potential impacts of the proposed pruning on the health, structure and amenity of the tree should also be considered.

6.2    If a condition is observed requiring attention beyond the original scope of the work, the condition should be reported to an immediate supervisor, the owner, or the person responsible for authorizing the work.


7    TOOLS AND EQUIPMENT

7.1    Pruning tools adequate for the size of cuts being made should be selected.

7.2    Equipment and work practices that damage living tissue and bark beyond the scope of the work should be avoided.

7.3    Sharp tools shall be used at all times so that clean cuts will be made.

8    PRUNING CUTS


8.1    A pruning cut that removes a branch at its point of origin shall be made as close as possible to the branch collar without cutting into the branch collar or branch bark ridge or leaving a stub.











8.2    A pruning cut that reduces the length of a branch or parent stem should bisect the angle between its branch bark ridge and an imaginary line perpendicular to the branch or stem.




8.3    The final cut shall result in a flat surface with adjacent bark firmly attached.

8.4    Pre-cutting: To avoid splitting or tearing of the branch collar or trunk, branches should be precut or undercut. The remaining stub is then removed with a final cut.





8.5    When removing a dead branch, the final cut shall be made just outside the branch collar.




8.6    A final cut that removes a branch with a narrow angle of attachment should be made from the outside of the branch to prevent damage to the parent limb.



8.9    Tree branches shall be removed in such a manner so as not to cause damage to other parts of the tree or to other plants or property. Branches too large to support with one hand shall be pre cut to avoid splitting of the wood or tearing of the bark. Where necessary, ropes or other equipment shall be used to lower large branches or portions of branches to the ground.

8.10    Severed limbs shall be removed from the crown upon completion of the pruning, at times when the tree would be left unattended, or at the end of the workday.


9    WOUND TREATMENT

9.1    Wound treatments should not be used to cover wounds or pruning cuts, except when recommended for disease, insect, mistletoe, or sprout control, or for cosmetic reasons.

9.2    Wound treatments that are damaging to tree tissues shall not be used.

9.3    When tracing wounds, only loose, damaged tissue should be removed.


10    PRUNING OBJECTIVES


10.1    Pruning objectives shall be established prior to beginning any pruning operation.

10.2    To obtain the defined objective, the growth cycles, health, form and structure of individual species and the type of pruning to be performed should be considered.

10.3    Not more than 30 percent of the foliage should be removed within an annual growing season. The percentage and distribution of foliage to be removed shall be adjusted according to the plant's species, age, health and site.

10.4    Not more than 30 percent of the foliage of a branch or limb should be removed when it is cutback to a lateral. That lateral should be at least one-third the diameter of the parent stem or branch to be removed and should be large enough to assume apical dominance.

10.5    All pruning cuts should be made in accordance with clause 8 (Pruning cuts).

10.6    Topping and lion's tailing shall be considered unacceptable pruning practices for trees.


11    TYPES OF PRUNING

11.1    The reasons for pruning should be considered before selecting or implementing the type of pruning. More than one type of pruning may be required for a particular tree.

11.2    Crown Cleaning: Cleaning shall consist of selective pruning to remove one or more of the following parts: dead, diseased, and/or broken branches.

11.2.1    Location of parts to be removed shall be specified.

11.2.2    Size range of parts to be removed shall be specified.

11.3    Crown Thinning: Thinning shall include crown cleaning as well as selective removal of branches to reduce density of live branches.

11.3.1    Thinning should result in an even distribution of branches on individual limbs and throughout the crown.

11.3.2    Not more than 25 percent of the crown should be removed within an annual growing season.

11.3.3    Location of parts to be removed shall be specified.

11.3.4    Percentage of foliage and size range of parts to be removed shall be specified.

11.4    Crown Raising: Raising shall consist of selective pruning to provide vertical clearance.

11.4.1    Vertical clearance should be specified.

11.4.2    Location and size range of parts to be removed should be specified.

11.5    Crown Reduction: Reduction shall consist of selective pruning to decrease height and/or spread.

11.5.1    The cut shall be made to a lateral that is at least one-third the diameter of the branch or stem being reduced.

11.5.2    Consideration shall be given to the ability of a species to tolerate this type of pruning?

11.5.3    Location of parts to be removed and clearance should be specified.

11.5.4    Size range of parts should be specified.


12    Pruning Young Trees

12.1    The reasons for young tree pruning may include, but are not limited to, promoting good structure, reducing risk, maintaining or improving tree health, improving aesthetics, or satisfying a specific need?


12.2    All broken, dead, dying or damaged branches shall be removed.

12.3    A dominant leader shall be established and maintained by subordinating or removing other competing stems.

12.4    The lowest permanent branch is selected and established. The height of this branch is determined by the location and intended function of the tree.

12.5    The main scaffold shall be identified and established by removing or shortening nearby branches. The branches should be selected for good attachment, appropriate size and proper spacing. Scaffold branches should be well spaced vertically and radially.

12.6    Temporary branches, below the lowest permanent branch and among the scaffold branches are selected and subordinated. Temporary branches shall be removed in later years.

12.7    All branches shall be prevented from growing larger than half the trunk diameter.

12.8    Live crown ratio of greater than 60 percent shall be maintained.


13    Pollarding

13.1    Consideration shall be given to the ability of the individual tree to respond to pollarding.

13.2    Management plans shall be made prior to the start of the pollarding process for routine removal of watersprouts.

13.3    Internodal cuts shall be made at specific locations to start the pollarding process. After the initial cuts are made, no additional internodal cut shall be made.

13.4    Watersprouts growing from the cut ends of branches (knuckles) should be removed annually during the dormant season.

 

 


 

 

Partners

Banner
Banner

Calendar

«   November 2017   »
SuMoTuWeThFrSa
   1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
  

more ...

JOIN US

Banner

ISA

Banner
mod_vvisit_countermod_vvisit_countermod_vvisit_countermod_vvisit_countermod_vvisit_countermod_vvisit_countermod_vvisit_countermod_vvisit_countermod_vvisit_counter
We have: 147 guests online
Your IP: 54.80.146.251
Today: Nov 18, 2017