AHCARB601
Examine and assess trees


Application

This unit of competency describes the skills and knowledge required to examine and assess tree health, age, taxonomy, risk, amenity value and significance and compile a tree assessment report.

This unit applies to individuals with broad theoretical and technical knowledge of a specific area or a broad field of work and learning and cognitive, technical and communication skills to demonstrate autonomy, judgement and defined responsibility in undertaking complex work within broad parameters to provide specialist advice and functions.

The role involves the self-directed application of knowledge with substantial depth in areas such as tree identification, pathology and diagnostics, tree assessment and valuation techniques, tree risk assessment and reporting methods.

Licensing, legislative, regulatory, or certification requirements apply to this unit in some states & territories at the time of publication, and may differ according to jurisdiction. Specific determination should be sought through the relevant State or Territory. Works involving this unit of competency may be subject to local tree protection and preservation laws, and the relevant content of applicable Australian Standards.


Elements and Performance Criteria

Element

Performance criteria

Elements describe the essential outcomes.

Performance criteria describe the performance needed to demonstrate achievement of the element.

1. Determine tree survey program requirements

1.1 Identify scope of survey in accordance with client needs

1.2 Determine client’s risk threshold

1.3 Determine and document procedures for data capture

1.4 Identify, source and record all current data research relevant to survey requirements

1.5 Check equipment for assessing trees and prepare for use

1.6 Select, check and use personal protective equipment

2. Determine the tree dimensions and structure

2.1 Plot tree location on a device, drawing or plan of the site

2.2 Determine and record tree dimensions and structure

2.3 Measure tree height, spread and diameter-at-breast height (DBH)

2.4 Examine and record form of tree

2.5 Assess tree for asymmetry of canopy

2.6 Assess if tree has a lean and calculate the lean

2.7 Assess how form of crown relates to or is responsive to surrounding trees and structures

2.8 Determine the potential impact of wind loading of the tree

3. Record tree taxonomic features

3.1 Inspect tree and record fruit type and characteristics

3.2 Describe leaf morphology for shape, colour and size

3.3 Examine and record buds, branchlets, branches and bark

3.4 Inspect for and describe trichomes on lamina, petiole and branchlets

3.5 Describe and record floral characteristics of structure of inflorescence, location of the flower, flower colour, details of the flower parts present, absent or modified

4. Assess tree health issues

4.1 Examine and record the canopy density and distribution

4.2 Assess recorded leaf colour and size against a healthy specimen

4.3 Assess for the presence of epicormic shoots

4.4 Assess for dead tips or excessive numbers of dead branches

4.5 Examine roots, root crown, stem, branches and canopy for signs of biotic and abiotic disease

4.6 Evaluate and describe symptoms presenting on tree

4.7 Determine how presence of disease might be affecting tree

4.8 Recognise and record wounds to the tree

4.9 Consider size, location and cause of wounds

5. Assess age of trees and tree parts

5.1 Determine if species is uninodal or multimodal

5.2 Record the dimensions of the tree

5.3 Examine tree for evidence of growth increments including bud scars, sympodial growth and flush marks

5.4 Estimate average annual increase in diameter of sample of xylem stained as required

5.5 Research historic images of tree or trees of same species in similar environments

5.6 Provide a reasoned estimate of age of tree, tree part or wound

6. Assess trees for significance

6.1 Assess tree for indicators of habitat use

6.2 Assess tree for ecological significance

6.3 Assess tree for cultural significance

6.4 Assess tree for historical significance

7. Assess amenity value of trees

7.1 Evaluate amenity tree valuation methods

7.2 Consider strengths and weaknesses of each method

7.3 Determine amenity tree valuation method to be used

7.4 Collect and collate appropriate unit values and data

7.5 Calculate and record the amenity value of individual trees

8. Inspect and assess trees

8.1 Assess trees to determine their structure and stability

8.2 Give consideration to the tree's age, health, condition, habitat, wind loading, distribution of foliage, wound size and the potential impacts of proposed recommendations

8.3 Use testing equipment, where required, to detect decay, disease and scope of tree problems

8.4 Evaluate visual indications and causes of disease and record results

9. Carry out risk assessment

9.1 Use visual tree assessment (VTA) to identify hazards associated with the tree

9.2 Use basic diagnostic tools to confirm the presence and extent of hazards

9.3 Determine level of risk

9.4 Give consideration to qualification and quantification of tree risk

9.5 Compare the risk level against commonly published levels of risk from non-arboricultural activities and items

9.6 Determine controls required to mitigate risks in accordance with the client’s pre-determined threshold

9.7 Document risk controls and recommendations for monitoring and review of risks

10. Compile a tree assessment report

10.1 Document diagnosis of tree problems with reference to the anatomy, physiology and pathology of the tree

10.2 Provide and record specific recommendations for remedial action for tree problems

10.3 Produce a tree assessment report that identifies hazardous trees, recommends appropriate remedial action, and determines appropriate risk controls

10.4 Prepare an expert witness statement if required

10.5 Deliver tree assessment report to client

Evidence of Performance

The candidate must be observed inspecting and assessing a broad range of trees for identification, health, growth habit, structure, stability and indications of disease. The candidate must be assessed on their ability to integrate and apply the performance requirements of this unit in a workplace setting. Performance must be demonstrated consistently over time and in a suitable range of contexts.

The candidate must provide evidence for and demonstrate:

identifying the scope of survey

determining the client’s risk threshold

documentation of the data capture procedures

identifying, sourcing and recording all current data research relevant to survey requirements

checking equipment for assessing trees and prepare for use

selecting, checking and using personal protective equipment

plotting tree locations on a device, drawing or plan of the site

determining the tree dimensions and structure

measuring the tree height, spread and diameter-at-breast height (DBH)

examining and recording form of tree

assessing tree for asymmetry of canopy

assessing if tree has a lean and calculate the lean

assessing how form of crown relates to or is responsive to surrounding trees and structures

determining the potential impact of wind loading of the tree

inspecting tree and record fruit type and characteristics

describing leaf morphology for shape, colour and size

examining and recording buds, branchlets, branches and bark

inspecting for and describing trichomes on lamina, petiole and branchlets

describing and recording floral characteristics of structure of inflorescence, location of the flower, flower colour, details of the flower parts present, absent or modified

examining and record the canopy density and distribution

assessing recorded leaf colour and size against a healthy specimen

assessing for the presence of epicormic shoots

assessing for dead tips or excessive numbers of dead branches

examining roots, root crown, stem, branches and canopy for signs of biotic and abiotic disease

evaluating and describing symptoms presenting on tree

determining how presence of disease might be affecting tree

recognising and recording wounds to the tree

considering size, location and cause of wounds

determining if species is uninodal or multimodal

recording the dimensions of the tree

examining tree for evidence of growth increments including bud scars, sympodial growth and flush marks

estimating average annual increase in diameter of sample of xylem stained as required

researching historic images of tree or trees of same species in similar environments

providing a reasoned estimate of age of tree, tree part or wound

assessing tree for indicators of habitat use

assessing tree for ecological significance

assessing tree for cultural significance

assessing tree for historical significance

evaluating various amenity tree valuation methods

considering strengths and weaknesses of each method

determining amenity tree valuation method to be used

collecting and collating appropriate unit values and data

calculating and recording the amenity value of individual trees

assessing trees to determine their structure and stability

consideration of the tree's age, condition, habitat, wind loading, distribution of foliage, wound size and the potential impacts of proposed recommendations

using testing equipment to detect decay, disease and scope of tree problems

evaluating visual indications of disease and health issues in trees

use of visual tree assessment (VTA) method to identify hazards

use of basic diagnostic tools to confirm the presence and extent of hazards

determining level of risk

giving consideration to qualification and quantification of tree risk

comparing the risk level against commonly published levels of risk from non-arboricultural activities and items

determining controls required to mitigate risks in accordance with the client’s pre-determined threshold

documenting risk controls and recommendations for monitoring and review of risks

documenting diagnoses of tree problems with reference to the anatomy, physiology and pathology of the tree

recording specific recommendations for remedial action for tree problems

producing a tree assessment report that identifies a hazardous tree and contains recommendations for appropriate remedial actions and risk controls

preparing an expert witness statement

use of industry standard terminology to describe arboriculture and the work environment.


Evidence of Knowledge

The candidate must demonstrate knowledge of:

risk thresholds

data capture procedures

survey requirements

tree assessment equipment

plotting methods on devices, drawings and plans

tree morphology attributes: fruit type and characteristics, leaf morphology for shape, colour and size, trichomes on lamina, petiole and branchlets, floral characteristics of structure of inflorescence, location of the flower, flower colour, details of the flower parts present, absent or modified, buds, branchlets, branches and bark

canopy density and distribution

comparison of leaf colour and size against a healthy specimen

epicormic shoots

examination of roots, root crown, stem, branches and canopy for signs of biotic and abiotic disease

disease symptoms

affect of disease on tree

tree dimensions and structure

tree height, spread and diameter-at-breast height (DBH)

form and morphology of tree

symmetry and asymmetry of canopy

calculation of tree lean

relationship of form of crown to surrounding trees and structures

responsiveness of form of crown to surrounding trees and structures

determination the potential impact of wind loading of the tree

tree wound recognition, size, location and cause

uninodal and multimodal tree species

growth increments including bud scars, sympodial growth and flush marks

estimation average annual increase in tree diameter

xylem staining

research of historic images of tree or trees of same species in similar environments

assessment of tree indicators of habitat use

assessment of tree ecological significance

assessment of tree cultural significance

assessment of tree historical significance

evaluation of methods of amenity tree valuation

calculation of amenity tree value of individual trees

tree structure and stability

tree assessment attributes: tree's identification, age, health, condition, habitat, wind loading, distribution of foliage, wound size and the potential impacts of proposed recommendations

testing equipment to detect decay, disease and scope of tree problems

visual indications and symptoms of disease and health issues

tree diseases

visual tree assessment (VTA)

methods of detecting decay and structural defects in trees

causes of instability, decay, damage and stress in trees

use of basic diagnostic tools

identification and extent of tree hazards

methods of determination of levels of risk

quantification and qualification of tree risk

commonly published levels of risk from non-arboricultural activities and items

controls required to mitigate risks in accordance with the client’s pre-determined threshold

diagnoses of tree problems

tree anatomy, physiology and pathology

remedial action of tree problems

production of a tree assessment report that identifies hazardous trees, recommends appropriate remedial action, and determines appropriate risk controls

preparation of an expert witness statement.


Assessment Conditions

Assessment must be demonstrated consistently over time in a suitable range of contexts and have a productivity-based outcome. No single assessment event or report is sufficient to achieve competency in this unit.

Assessment may be conducted in a simulated or real work environment, however determination of competency requires the application of work practices under work conditions.

The mandatory equipment and materials used to gather evidence for assessment include:

equipment:

computer

word processing software

internet connection

digital camera with macro

personal protective equipment (PPE)

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

cross-sectioned defects and diseases

soil testing equipment

basic digital dissection microscope 10 -100x

compound microscope

microtome, staining and slide mounting equipment

slides and coverslips

temporary/permanent mountant

histochemical stains

materials:

tree assessment report

tree profile and benefits form

disease profile form

Assessors must satisfy current standards for RTOs in the assessment of arboriculture units of competency.

Assessment must be conducted only by persons who have:

arboriculture vocational competencies at least to the level being assessed

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


Foundation Skills

Foundation Skills essential to performance are explicit in the performance criteria of this unit of competency.


Range Statement


Sectors

Arboriculture (ARB)