Using the Revised ANSI A300
Using the Revised ANSI A300
Pruning Standard to Write
Pruning Standard to Write
Effective Specifications
Effective Specifications
Geoff Kempter
Asplundh Technical Services
Background
Arborists provide
professional services
Standards of performance
apply
Using ANSI A300
Standards as the basis for
specifications and training
will improve your service!
Do you use ANSI A300 Standards?
Do you use work specifications?
Is there a difference?
Standard vs. Specification
Standard vs. Specification
(From Google)
(From Google)
Specification
Standard
Describing or identifying
something precisely
Stating a precise requirement
A detailed description of the
design and materials used to
make something
A standard of workmanship,
materials, etc., required to be
met in a piece of work
A level of quality or
attainment
Something used as
a measure, norm,
or model in
comparative
evaluations.
Background
ANSI Standards
ANSI is a private, nonprofit that helps American industry
develop voluntary consensus standards
Standards are not mandatory, unless they are adopted
as regulations.
ANSI does not write industry standards.
ANSI requires certain processes to assure that standards
are fair and effective.
ANSI audits organizations that publish ANSI standards to
assure compliance.
Requirements (recordkeeping, processes, etc.) are quite
rigorous.
ANSI Standards
According to
ANSI, there are
over 10,000
published ANSI
Standards!
A sampling of standards from other industries
A sampling of standards from other industries
ANSI Z136.1: Safe Use of Lasers
A sampling of standards from other industries
NSF/ANSI 140: Sustainability Assessment for Carpet
A sampling of standards from other industries
ANSI X12: Electronic Data Exchange
A sampling of standards from other industries
ANSI N13.36 Ionizing Radiation Safety Training
A sampling of standards from other industries
ANSI/NEMA FL 1: Flashlight performance
A sampling of standards from other industries
ANSI/BIFMA X5.1: Office Seating
A sampling of standards from other industries
ANSI B 29.1: Roller Chains
These standards all use the ANSI process.
ANSI Z136.1: Safe Use of Lasers
NSF/ANSI 140: Sustainability Assessment for Carpet
ANSI X12: Electronic Data Exchange
ANSI N13.36 Ionizing Radiation Safety Training for
Workers
ANSI/NEMA FL 1: Flashlight performance
ANSI/BIFMA X5.1: Office Seating
ANSI B 29.1: Roller Chains
Newly Proposed ANSI Standard:
…There is broad-based
support among key
stakeholders … for ANSI
to establish an
Unmanned Aircraft
Systems (UAS)
Standardization
Collaborative (UASSC).
-ANSI.org
ANSI “Cardinal Principles”
Consensus –
Achieved by a balanced
committee representing
affected and interested parties
Openness –
Any member of the public may
submit comments during public
review periods
Transparency –
Comments must be reviewed
and responded to by the
committee in good faith
Due Process –
An appeals process is required
Due Process
Openness
Transparency
Consensus
A300
A300
Tree Care
Tree Care
u
u
Since
Since
1995, TCIA Secretariat
1995, TCIA Secretariat
u
u
Defines standard practices for
Defines standard practices for
tree care
tree care
u
u
Applies to
Applies to
professional
professional
practitioners of arboriculture,
practitioners of arboriculture,
including utilities
including utilities
u
u
Uses:
Uses:
To develop specifications,
To develop specifications,
training programs and
training programs and
regulations as appropriate
regulations as appropriate
Ø
Ø
Bottom line: Whatever you
Bottom line: Whatever you
do, do it right!
do, do it right!
Z133
Z133
Safety
Safety
u
u
Since
Since
1972, ISA Secretariat
1972, ISA Secretariat
u
u
Provides
Provides
safety criteria
safety criteria
for
for
tree work
tree work
u
u
Applies to
Applies to
employers and
employers and
employees
employees
in arboriculture
in arboriculture
u
u
Uses:
Uses:
To develop effective
To develop effective
safety training programs
safety training programs
By government to create
By government to create
safety regulations
safety regulations
Ø
Ø
Bottom line: Whatever you
Bottom line: Whatever you
do, do it safely!
do, do it safely!
ANSI Standards for Arborists
ANSI Standards for Arborists
ANSI A300 Standards
Part 1, Pruning
Part 2, Soil Management (Fertilization)
Part 3, Tree Support Systems
Part 4, Lightning Protection
Part 5, Management (During Construction)
Part 6, Transplanting
Part 7, Integrated Vegetation Management
Part 8, Root and Root Zone Management
Part 9, Tree Risk Assessment
Part 10, Plant Health Care
ANSI A300 Standards
For professionals
Assumes basic knowledge and
capability
Technical language
Not for public consumption
Designed for flexibility
Because with trees, every
situation is different
Designed to create effective
specifications and training
programs to meet the needs of
you and your customers
ANSI A300 Standards
Are NOT:
Specifications!
Specs describe in detail what must
be done, including:
Sizes, locations, distances, percentages
etc.
“How to” guides
Standards contain minimal words
and descriptions
If you want to know “how to,” buy a
book!
Does our industry
need standards?
Business card
from a local
tree service
Does our industry need standards?
Does our industry need standards?
Background
Revision of Part 1, Pruning
A300 Standards are periodically
revised (improved!)
Pruning last revised in 2008,
renewed 2014
2017 version now approved
and available this year
There are substantial changes!
A300 Part 1
Changes
A300 Part 1
Changes
OPPORTUNITY
To learn how the
Standard should be
used
To improve
specifications and
overall performance
2017 A300 Pruning Revision
2017 A300 Pruning Revision
Change in flow to better reflect field work
Change in flow to better reflect field work
A300 Pruning starts like this:
Forward
1. ANSI A300 – Scope and purpose of the Standard
2. ANSI A300 Pruning Standards, purpose, application, safety
3. Normative References
Federal laws and other standards as they apply, and are
included by reference, e.g.
All other A300 Parts
ANSI Z133
29 CFR OSHA 1910
Migratory Bird Treaty Act
Endangered Species Act
Old Structure
Old Structure
Structure Comparison
Structure Comparison
Changes
Changes
Elimination of “Pruning Methods”
Elimination of “Pruning Methods”
2008: “One or more of
the following methods
shall be specified to
achieve the objective:”
o Clean
o Raise
o Reduce
o Thin
These terms are ambiguous and
were often confused with objectives
Changes
Changes
Elimination of “Pruning Methods”
Elimination of “Pruning Methods”
Instead, specify objectives, e.g.
o “Clean the crown” or…
Ø Reduce risk by removing dead branches >2…”
o “Thin crown” or….
Ø Reduce density of live ranches above roof by 20%...
o “Raise crown”
Ø Provide 15’ clearance over roadway…
o “Reduce crown”
Ø Reduce height (length) by (amount)…
These terms can be used in specifications, however, the
standard no longer requires you to specify one or more
Elimination of Utility Pruning
Elimination of Utility Pruning
Elimination of Utility Pruning
Elimination of Utility Pruning
All arborists perform
utility-style pruning, e.g.
o Clearance, from
other plants,
buildings, raising for
traffic, etc.
o Reduction
o Views and other lines
of sight
Utility pruning is now
integrated into the
standard.
9 Utility pruning
9.1 Purpose
The purpose of utility pruning is to prevent the loss of service, comply with mandated clearance laws, prevent damage to equipment, maintain access,
and uphold the intended usage of the facility/utility space while adhering to accepted tree care performance standards.
9.2 General
9.2.1 Only a qualified line-clearance arborist or line-clearance arborist trainee shall be assigned to line clearance work in accordance with ANSI Z133.1,
29 CFR 1910.331 – 335, 29 CFR 1910.268 or 29 CFR 1910.269.
9.2.2 Utility pruning operations are exempt from requirements in subclause 5.1, Tree Inspection, for conditions outside the utility pruning scope of
work.
9.2.3 Job briefings shall be performed as outlined in ANSI Z133.1, subclause 3.1.4.
9.3 Utility crown reduction pruning
9.3.1 Urban/residential areas
9.3.1.1 Pruning cuts should be made in accordance with subclause 5.3, Pruning cuts. The following requirements and recommendations of 9.3.1.1 are
repeated from subclause 5.3 Pruning cuts.
9.3.1.1.1 A pruning cut that removes a branch at its point of origin shall be made close to the trunk or parent branch, without cutting into the branch
bark ridge or collar, or leaving a stub (see Figure 5.3.2).
9.3.1.1.2 A pruning cut that reduces the length of a branch or parent stem shall be made at a slight downward angle relative to the remaining stem
and not damage the remaining stem. Smaller cuts shall be preferred (see Fig. 5.3.3).
9.3.1.1.3 The final cut shall result in a flat surface with adjacent bark firmly attached.
9.3.1.1.4 When removing a dead branch, the final cut shall be made just outside the collar of living tissue.
9.3.1.1.5 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 precut to avoid splitting of the wood or tearing of the bark (see Figure 5.3.2). Where necessary,
ropes or other equipment shall be used to lower large branches or portions of branches to the ground.
9.3.1.1.6 A 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 branch (see Figure 5.3.8).
9.3.1.2 A minimum number of pruning cuts should be made to accomplish the purpose of facility/utility pruning. The structure and growth habit of the
tree should be considered. 9.3.1.3 Trees directly under and growing into facility/utility spaces should be removed or pruned. Such pruning should be
done by removing entire branches or leaders or by removing branches that have laterals growing into (or once pruned, will grow into) the
facility/utility space.
9.3.1.4 Trees growing next to, and into or toward, facility/utility spaces should be pruned by reducing branches to laterals (5.3.3) to direct growth
away from the utility space or by removing entire branches. Branches that, when cut, will produce sprouts that would grow into facilities and/or utility
space should be removed.
9.3.1.5 Branches should be cut to laterals or the parent branch and not at a pre-established clearing limit. If clearance limits are established, pruning
cuts should be made at laterals or parent branches outside the specified clearance zone.
9.3.2 Rural/remote locations – mechanical pruning
Cuts should be made close to the main stem, outside of th branch bark ridge and branch collar. Precautions should be taken to avoid stripping or
tearing of bark or excessive wounding.
9.4 Emergency service restoration
During a utility-declared emergency, service must be restored as quickly as possible in accordance with ANSI Z133.1, 29 CFR 1910.331 – 335, 29 CFR
1910.268, or 29 CFR 1910.269. At such times, it may be necessary, because of safety and the urgency of service restoration, to deviate from the use of
proper pruning techniques as defined in this standard. Following the emergency, corrective pruning should be ddone as necessary.
9 Utility pruning
9.1 Purpose
The purpose of utility pruning is to prevent the loss of service, comply with mandated clearance laws, prevent damage to equipment, maintain access,
and uphold the intended usage of the facility/utility space while adhering to accepted tree care performance standards.
9.2 General
9.2.1 Only a qualified line-clearance arborist or line-clearance arborist trainee shall be assigned to line clearance work in accordance with ANSI Z133.1,
29 CFR 1910.331 – 335, 29 CFR 1910.268 or 29 CFR 1910.269.
9.2.2 Utility pruning operations are exempt from requirements in subclause 5.1, Tree Inspection, for conditions outside the utility pruning scope of
work.
9.2.3 Job briefings shall be performed as outlined in ANSI Z133.1, subclause 3.1.4.
9.3 Utility crown reduction pruning
9.3.1 Urban/residential areas
9.3.1.1 Pruning cuts should be made in accordance with subclause 5.3, Pruning cuts. The following requirements and recommendations of 9.3.1.1 are
repeated from subclause 5.3 Pruning cuts.
9.3.1.1.1 A pruning cut that removes a branch at its point of origin shall be made close to the trunk or parent branch, without cutting into the branch
bark ridge or collar, or leaving a stub (see Figure 5.3.2).
9.3.1.1.2 A pruning cut that reduces the length of a branch or parent stem shall be made at a slight downward angle relative to the remaining stem
and not damage the remaining stem. Smaller cuts shall be preferred (see Fig. 5.3.3).
9.3.1.1.3 The final cut shall result in a flat surface with adjacent bark firmly attached.
9.3.1.1.4 When removing a dead branch, the final cut shall be made just outside the collar of living tissue.
9.3.1.1.5 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 precut to avoid splitting of the wood or tearing of the bark (see Figure 5.3.2). Where necessary,
ropes or other equipment shall be used to lower large branches or portions of branches to the ground.
9.3.1.1.6 A 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 branch (see Figure 5.3.8).
9.3.1.2 A minimum number of pruning cuts should be made to accomplish the purpose of facility/utility pruning. The structure and growth habit of the
tree should be considered. 9.3.1.3 Trees directly under and growing into facility/utility spaces should be removed or pruned. Such pruning should be
done by removing entire branches or leaders or by removing branches that have laterals growing into (or once pruned, will grow into) the
facility/utility space.
9.3.1.4 Trees growing next to, and into or toward, facility/utility spaces should be pruned by reducing branches to laterals (5.3.3) to direct growth
away from the utility space or by removing entire branches. Branches that, when cut, will produce sprouts that would grow into facilities and/or utility
space should be removed.
9.3.1.5 Branches should be cut to laterals or the parent branch and not at a pre-established clearing limit. If clearance limits are established, pruning
cuts should be made at laterals or parent branches outside the specified clearance zone.
9.3.2 Rural/remote locations – mechanical pruning
Cuts should be made close to the main stem, outside of th branch bark ridge and branch collar. Precautions should be taken to avoid stripping or
tearing of bark or excessive wounding.
9.4 Emergency service restoration
During a utility-declared emergency, service must be restored as quickly as possible in accordance with ANSI Z133.1, 29 CFR 1910.331 – 335, 29 CFR
1910.268, or 29 CFR 1910.269. At such times, it may be necessary, because of safety and the urgency of service restoration, to deviate from the use of
proper pruning techniques as defined in this standard. Following the emergency, corrective pruning should be done as necessary.
Normative reference
Repeated elsewhere in
standard
Useful - moved elsewhere in standard
2017 Revision:
“Clearance pruning” – applications beyond utility
pruning
8.7.1 Branches growing toward
specified clearance areas should be
reduced to lateral branches or
removed to parent stems growing
outside and/or away from the
clearance area (directional pruning).
8.7.2 When a minimum clearance
distance is required, a branch
removal or reduction cut should be
made beyond the specified clearance
distance at a suitable branch union.
2017 Revision
“Clearance pruning” – applications beyond utility
pruning
8.7.2.1 When a reduction
cut cannot be made to a
suitable lateral branch,
and to avoid an
unnecessarily large
pruning cut at the parent
stem, a heading cut should
be considered.
4. Pruning Objectives
4. Pruning Objectives
i.e
i.e
.
.
why the work is needed
why the work is needed
Revision changes:
Objectives moved forward
Expanded list of objectives
Expanded sample
specifications in annex.
What are some
typical pruning
objectives?
Stating objectives in specifications avoids
misunderstandings and confusion between
o Bosses and crews
o Companies and customers
o Regulatory agencies and constituents
4. Pruning Objectives
“One or more pruning objectives shall be specified…”
Manage risk (A300 Part 9, Tree Risk Assessment).
Manage health.
Develop structure, such as to:
Improve branch and trunk architecture;
Promote or subordinate certain leaders, stems or
branches;
Promote desirable branch spacing;
Promote or discourage growth in a particular
direction (directional pruning);
Minimize future conflict with traffic or infrastructure;
Restore plants following damage; and/or,;
Rejuvenate shrubs.
4. Pruning Objectives
“One or more pruning objectives shall be specified…”
Provide clearance, such as to:
Ensure safe and reliable utility services;
Minimize current interference with infrastructure,
buildings or other plants;
Raise crown(s) for movement of traffic or light
penetration;
Ensure lines-of-sight or desired views;
Provide access to sites, buildings or other structures;
and/or,
Comply with regulations.
Manage size or shape.
Improve aesthetics.
Manage production of fruit, flowers, or other products.
Manage wildlife habitat.
NEW:
NEW:
5. Pruning Systems
5. Pruning Systems
“A pruning system should be specified to achieve
the desired long-term form of the plant”
Pruning System – “Process used to achieve
the desired long term form of the plant.”
5. Pruning Systems
What are some
pruning systems?
Bonsai (not in A300)
5. Pruning Systems
Pollarding:
A pruning system that
maintains crown size by initial
heading of branches on young
trees, followed by removal of
shoots to their point of origin
at appropriate intervals
without disturbing the resulting
pollard head.
5. Pruning Systems
Topiary
The combination of
pruning, supporting,
and training branches
to orient a plant into a
desired shape.
Hedging is a form of
topiary
5. Pruning Systems
Espalier
A pruning system that
trains plants to grow
within a plane, such as
along a wall or fence.
5. Pruning
Systems
Pleaching
Pruning system that trains one or
more plants to achieve a desired
shape or form through a
combination of pruning and
interweaving or tying small
branches to one another, or to a
pre-formed frame.
5. Pruning Systems
“Natural”
“A natural system
should maintain the
characteristic
growth pattern and
adaptations of the
plant.”
The majority of trees are pruned using the Natural System
5. Pruning Systems
Natural
5. Pruning Systems
Natural
5. Systems
Natural
5. Pruning Systems
Natural
Natural System:
Natural System:
“A natural system should allow for
changes in appearance resulting from
pruning when achieving certain
specified objectives, such as:
o Raising crowns
o Crown or branch reduction
o Enhancing views
o Developing or improving structure
o Providing clearance
o Risk reduction “
5. Pruning Systems
Natural
Pollarding
Topiary
Espalier
Pleaching
Natural
Unnatural
NEW!
6. Pruning Specifications
Specifications should include:
Jobsite location – (WHERE)
Pruning objectives – (WHY)
Pruning system – (HOW)
WHAT , WHERE in crown, and HOW MUCH to prune
Plan for disposal/repurposing of debris
Time frame for completion - (WHEN)
Other information as necessary (e.g. clearance
distances, view lines of sight, mechanical pruning).
6. Pruning Specifications
Guidance on amount to prune:
25% guideline eliminated
4.2 Pruning operations should remove no
more living material than what is necessary to
achieve specified objectives.
4.3 Species, size, age, condition, and site shall
be considered when specifying the location and
amount of live branches to be removed.
Old version:
“…Not more
than 25% of the
crown should
be removed….”
NEW!
NEW!
7. Pruning Cuts
7. Pruning Cuts
Branch
Removal Cut
Reduction cut
Heading cut
Shearing cut
The revision also names and describes a “Flush Cut”
as an unacceptable practice
7. Pruning Cuts
Branch Removal Cut
…removes the smaller of
two branches at a union,
or a parent stem….
without cutting into the
branch bark ridge or
branch collar, or leaving
a stub
Bran
ch
colla
r
7. Pruning Cuts
Reduction Cut
…removes the larger of
two or more branches
or stems… to a live
lateral branch….
Branch
Removal
Cut
Reduction
Cuts
University of Florida
7. Pruning Cuts
Heading Cut
…removes a branch or stem
between nodes…to a bud,
or to a live branch typically
less than one-third the
diameter of the branch
being removed.
Colorado State University
University of Florida
7. Pruning Cuts
Shearing Cut
Cutting to a
desired plane or
shape, as with
topiary
Consider species
Cut only to
stems capable
of growing new
shoots
8. Pruning Practices
8. Pruning Practices
Inspection
Work Practices
o Climbing Spurs
o Wound Treatment
Clearance Pruning
Mechanical Pruning
Topping (unacceptable)
Lion Tailing (unacceptable)
Debris Disposal
Monitoring Interval
Emergency Operations
9. Pruning Palms and Similar Plants
9. Pruning Palms and Similar Plants
9.1 Dead, damaged, or loose
fronds should be pruned…
9.2 Healthy fronds should not be
removed…
9.3 Fruits that pose unacceptable
risk or nuisance, or
flowers…should be removed.
9.4 Palms that under normal
growing conditions could damage
critical infrastructure should be
pruned, growth regulated,
relocated, or removed.
9. Pruning Palms and Similar Plants
9.5 Yellowing fronds that are not
diseased or infested should be
retained, except when they pose safety
or aesthetic concerns.
9.5.1 Diseased or infested palms
should be treated, or fronds removed,
when necessary to reduce the spread
of pests and/or to protect the health of
the palm (see ANSI A300 Part 10, IPM).
9.6 …damaged green fronds that do
not pose unacceptable risk should be
retained…
9. Pruning Palms and Similar Plants
9.7 Fronds should be removed…without
damaging living trunk tissue.
9.7.1 …removal of palm frond skirts…shall
be performed from the top down (ANSI
Z133).
9.7.2 When removing dead petiole bases
(skinning, peeling), living trunk tissue
should not be damaged.
9.8 When there is a high potential to
spread pests, appropriate precautions
shall be taken.
9.8.1 Climbing spurs should not be used…
9.9 Disposal of debris should be specified
10. Definitions (what it all means)
10.1 arboriculture: The art, science, technology, and business of commercial,
public, and utility tree care.
10.2 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 and other woody plants.
10.3 arborist trainee: An individual undergoing on-the-job training to obtain the
experience and the competence required to provide for or supervise the
management of trees and other woody plants. Such trainees shall be under the
direct supervision of an arborist.
10.4 branch: A shoot or stem arising from another branch or stem (See Fig. xyz).
10.4.1 codominant stem/codominant branch: Two or more stems or
branches of similar diameter originating from the same union (See Fig. xyz).
10.4.2 lateral branch: A shoot or stem growing from a larger (parent)
branch (See Fig. xyz).
10.4.3 parent stem/branch A tree trunk, main stem, leader or branch
from which other smaller branches grow (See Fig. xyz).
Revised ANSI A300 Pruning Standard Flow
Revised ANSI A300 Pruning Standard Flow
A300 Revision – Summary of changes
Restructured for better flow
Greater emphasis on OBJECTIVES
Eliminated
“Pruning Methods (Types)”
“Utility Pruning”
Added:
“Specifications”
“Pruning Systems”
Available NOW
Pruning Specifications, e.g.
Jobsite location
Jones property, 111 Sandy Way, Coastaltown, OH
Pruning objectives
Reduce risk, increase light penetration
Pruning system
Natural
What , where in crown, and how much to prune
Reduce branches over roof to laterals
Remove dead branches >2” in entire crown
Remove lower branches over garden beds to achieve 12’
clearance
Plan for disposal/repurposing of debris
Chip all debris and leave on site next to garage
Time frame for completion
Work to be done on Monday, December 13
Other information as necessary, e.g. monitoring interval
Pruning Objectives?
Client: Hotel
Tree: Ficus, growing in front, entrance to hotel is under
the canopy of this tree.
Pruning Objectives
üreducing risk
üAesthetics/appearance
üclearance
üincrease light penetration
ümaintain tree health
Objectives are
determined by the
owner/client, with
input from the service
provider
reducing risk
aesthetics
clearance
increase light penetration
maintain tree health
Pruning Objectives
Should be clearly defined in job specifications!
Ø Job specs must comply with recognized industry
standards
This eliminates confusion, misunderstandings,
miscommunications, etc. between
Bosses and crews
Companies and clients
Regulatory agencies and constituents
Job Specifications
Remember:
What is obvious to YOU may not be
obvious to someone else!
Job Specifications
System:
ü Natural
Specification:
Objectives
üreducing risk
üAesthetics/appearance
üclearance
üincrease light penetration
ümaintain tree health
Inadequate specification – Prune Large Ficus in
front of Fairmont Hotel
Clean crown of dead, diseased and broken branches
Provide clearance between tree and adjacent building
Raise crown over walks and driveway
Reduce length of branches emerging from the crown
Thin crown
Maintain tree health
Prune to A300 Standards
Inadequate specification – Prune Large Ficus in
front of Fairmont Hotel
Clean crown of dead, diseased and broken branches (size, location?)
Provide clearance between tree and adjacent building (distance?)
Raise crown over walks and driveway (how far?)
Reduce length of branches emerging from the crown (how much?)
Thin crown (%?)
Maintain tree health (how?)
Prune to A300 Standards
Improved Specification, to explain where, what,
why, how much, e.g:
Reduce risk and improve health by removing dead, declining and
broken branches >1” diameter from the entire crown
Reduce length of branches to achieve a minimum of 5’ of clearance
between tree and adjacent building
Provide 12’ clearance over walks and driveway
Reduce length of branches emerging from the crown to assure visual
uniformity
Increase light penetration, using
reduction cuts
Ø Remove no more than 10%
of living foliage overall, or
on any specific branch/lead
Methods used shall comply with
applicable portions of A300,
part 1, 2008, Pruning (or latest
revision), as follows:…
Client: Corporate Campus
Client Objectives
Client Objectives
Risk reduction – pedestrians,
building
Clearance – from building,
walkway and adjacent tree
Reduce leaves falling onto
building roof
Assure health of tree
Specifications
System:
Natural
Specifications:
Objectives:
Risk reduction – pedestrians, building
Clearance –building, walkway, tree
Reduce leaves falling onto building roof
Assure health of tree
Inadequate Specification – Prune Red Maple on
East Side of Building
Clean crown of dead, diseased
and broken branches (size,
location?)
Prune tree away from building
and adjacent smaller tree
(distances?)
Raise crown above walkway
(how far?)
Thin crown (how much?)
Maintain tree health
Prune to A300 Standards
Improved Specification – Prune Red Maple on
East Side of Building
Reduce risk and improve health by removing dead, declining and
broken branches >1” in diameter from the entire crown.
Reduce branches growing toward building to provide min. of 6’
clearance. Prune to parent branches or laterals >50% diameter of
pruned branch
Raise crown to provide 10’ of
clearance above walkway
Thin crown above building by 25%
Remove no more than 25% of living
foliage overall, or on any specific
branch
Methods used shall comply with
applicable portions of A300, part 1,
2008, Pruning (or latest revision), as
follows:…
Street Tree Pruning - Objectives
Street Tree Pruning - Objectives
Risk reduction
Clearance
Vehicular, pedestrian, buildings, streetlights
Improve lines of sight
Signs, traffic, etc
Improve structure
Street Tree Pruning - Specifications
Inadequate Municipal Specification – Street Trees
Clean crowns to remove dead, diseased and broken branches (sizes?)
Raise crowns to provide clearance over street and sidewalks (how
much?)
Do not remove too much living foliage on any individual tree or
branch (how much is too much?)
Prune to improve structure:
üReduce or remove interfering,
defective, and poorly attached
branches (size?)
üReduce or remove competing
branches and leaders to develop
a strong scaffold branch
structure (spacing?)
Prune to A300 Standards
More Precise Municipal Specification – Street Trees
Reduce risk by removing dead, declining and broken branches >2”
diameter from tree crowns.
Provide a minimum of 15’ clearance above street from curb to curb,
and 10’ above sidewalks
Remove no more than 25% of living foliage on any individual tree or
branch
Prune to improve structure (trees <12” diameter only):
ü Reduce or remove interfering,
defective, and poorly attached
branches greater than 2”
diameter
ü Reduce or remove competing
branches and leaders to develop
strong scaffold branches with a
minimum 24” spacing
Methods used shall comply with
applicable portions of A300,
Part 1, etc…
Utility Pruning - Objectives
Utility Pruning - Objectives
Risk reduction
Clearance - safety
and reliability
Provide access to
facilities
Enhance line of sight
Utility Pruning Specification
Reduce risk, and attain 10’ or four years of clearance, whichever
is greater, by pruning branches under, alongside, or above
conductors.
Remove poorly attached, declining or dead branches 2” or
greater overhanging, alongside or that could otherwise contact
conductors
üEXCEPTION: On suitable species,
healthy leaders or scaffold branches
that pose low risk may be retained
within 10’ but not less than 2’
üClearance distances shall be adjusted
for the effect of wind, sagging of
conductors, ice load, etc. (National
Electric Safety Code)
Methods used shall comply with
applicable portions of A300, part 1,
2008, Pruning (or latest revision), as
follows:…
Utilities prioritize work specifications based
on line priority, e.g.:
High Priority Line,
low risk tolerance
70% of crown must
be removed to
achieve safe
clearance
Specification:
Remove poorly attached
branches that could contact
conductors…
Remove whole tree if possible,
however, removing all such trees
may not be feasible.
High Priority Line
Line Priority
Alternative spec:
Remove lower branches
encroaching on lines from
beneath at main trunk
Reduce length of upper
branches within strike
distance of line by 15-20% to
reduce weight
High to medium priority
line, moderate risk
tolerance
Alternative spec:
Remove lower branches
encroaching on lines from
beneath at main trunk
Remove closest branch to
lateral at old roundover
Lower priority line,
higher risk tolerance
Line Priority
Using the Revised ANSI A300
Using the Revised ANSI A300
Pruning Standard to Write
Pruning Standard to Write
Effective Specifications
Effective Specifications
Geoff Kempter
Asplundh Technical Services
Thanks! - Geoff Kempter - gkemp@asplundh.com
Specification Writing Exercise
Tree has been pruned for
line clearance
Customer desires remainder
of tree pruned
Specification
Jobsite location
Objectives
System
What, where in
crown, and how much
to prune, types of
cuts
Plan for disposal/
repurposing of debris
Time frame for
completion
Monitoring interval
Sidewalk replaced
Roots cut
Sidewalk replaced
Roots cut
Specification
Jobsite location
Objectives
System
What, where in crown,
and how much to
prune, types of cuts
Plan for disposal/
repurposing of debris
Time frame for
completion
Monitoring interval
Tree previously
rounded over
Specification
Jobsite location
Objectives
System
What, where in crown,
and how much to
prune, types of cuts
Plan for disposal/
repurposing of debris
Time frame for
completion
Monitoring interval
Tree pruned for line
clearance
Specification for pruning the
rest of the tree
Specification
Jobsite location
Objectives
System
What, where in crown,
and how much to
prune, types of cuts
Plan for disposal/
repurposing of debris
Time frame for
completion
Monitoring interval
Tree
recently
topped
Specification
Jobsite location
Objectives
System
What, where in crown,
and how much to
prune, types of cuts
Plan for disposal/
repurposing of debris
Time frame for
completion
Monitoring interval
Specification
Jobsite location
Objectives
System
What, where in crown,
and how much to
prune, types of cuts
Plan for disposal/
repurposing of debris
Time frame for
completion
Monitoring interval
Tulip poplar
Specification
Jobsite location
Objectives
System
What, where in crown,
and how much to
prune, types of cuts
Plan for disposal/
repurposing of debris
Time frame for
completion
Monitoring interval