Application
This unit of competency describes the skills and knowledge required to diagnose tree diseases and develop a management program for their control. Diseases include pathogens, pests and other disorders of angiosperms, gymnosperms and woody monocotyledons.
The unit applies to individuals who work in arboriculture and analyse information and exercise judgement to complete a range of advanced skilled activities and demonstrate deep knowledge in a specific technical area. They have accountability for the work of others and analyse, design and communicate solutions to a range of complex problems.
No licensing, legislative or certification requirements apply to this unit at the time of publication.
Elements and Performance Criteria
Elements | Performance Criteria |
1. Assess environmental impact | 1.1 Identify tree species and determine its region of origin and seasonal growth characteristics 1.2 Determine current and past cultural practices and impact on tree health 1.3 Determine characteristics of growing environment affecting growth of tree 1.4 Identify environmental and cultural factors predisposing tree to disease 1.5 Determine and assess physical and chemical properties of the soil or growing media |
2. Identify diseased trees | 2.1 Identify trees displaying disease symptoms 2.2 Recognise natural defence systems of trees for major disease types 2.3 Determine disease groups according to classification 2.4 Investigate trees for signs and symptoms of disease 2.5 Determine impact of disease type on tree parts and systems |
3. Diagnose tree disease | 3.1 Record symptoms and signs of disease according to accepted nomenclature 3.2 Collect and collate samples and evidence of disease and reference according to industry procedures 3.3 Determine the nature and severity of the disease condition 3.4 Determine disease type according to disease classification procedures 3.5 Research and identify disease according to industry standards 3.6 Prepare specimens of diseases for examination 3.7 Collect and package specimens in preparation for despatch to specialist for diagnosis and laboratory testing according to biosecurity procedures |
4. Provide a prognosis | 4.1 Determine the current health and vigour of the tree 4.2 Assess the severity and extent of the disease 4.3 Research the virulence of the disease on the specific host 4.4 Determine the phenology of the host and the disease 4.5 Research and consider constraints for management options 4.6 Consider influences of environmental conditions on host, disease and management options 4.7 Document prognosis and report according to workplace procedures |
5. Develop, document and monitor the management program | 5.1 Investigate and recommend management options 5.2 Develop a disease management program according to industry best practice 5.3 Record and document tree diseases and management programs according to workplace procedures 5.4 Monitor, review and update management plans |
Evidence of Performance
An individual demonstrating competency must satisfy all of the elements and performance criteria in this unit.
There must be evidence that individual has identified and collated representative samples of at least 30 diseases of trees, including evidence of infection, into a referenced collection, including:
10 invertebrate pests, including insects and molluscs
10 pathogenic organisms
10 environmental and soil disorders.
Where biosecurity is a concern, the sample can be replaced by a high quality informative image.
There must also be evidence that the individual has:
identified the affected tree and determined its origin and seasonal growth stages
determined factors affecting tree health and growth, which must include:
current and past cultural practices
characteristics of growing environment
environmental and cultural factors that predispose trees to disease
assessed physical and chemical properties of the soil or growing media
identified trees with diseases
recognised natural defence systems for major disease types
determined disease groups according to disease classification
investigated trees for signs and symptoms of disease
recorded symptoms and signs of disease using accepted nomenclature
determined impact of disease type on tree parts and systems
determined the nature and severity of the disease
determined disease type
researched and identified tree diseases
prepared specimens of diseases for microscopic examination
collected, packaged and prepared specimens for dispatch for specialist diagnosis or laboratory testing according to biosecurity procedures
determined current health and vigour of the tree
assessed severity and extent of the disease
researched virulence of the disease on the specific host
determined phenology of the host and the disease
researched and considered the constraints for management options
considered influences of environmental conditions on host, disease and management options
documented prognosis according to workplace procedures
investigated and recommended management options
developed a disease management program
recorded and documented tree diseases and management programs in a report
monitored, reviewed and updated management plan.
Evidence of Knowledge
An individual must be able to demonstrate the knowledge required to perform the tasks outlined in the elements and performance criteria of this unit. This includes knowledge of:
definition of disease and basic concepts of plant pathology, including:
plant pathogens, pests and disorders
macro organisms, microorganisms
disease classification guides
virulence, phenology, prognosis and disease severity and extent
economics and tree diseases
trees species; their growing environment and relationship to diseases, including:
taxonomic identification
tree anatomy, physiology, pathology
life cycle stages and characteristics of trees and their vulnerabilities
primary cellular and anatomical structures of trees
critical systems in trees and relationship to plant health, including physiological and biochemical
natural defence mechanisms and systems of trees
implications of growing season, climate and regional characteristics on tree species and disease development
cultural practices, including mulching, irrigation, pruning
impact of soil or media on tree health, including:
chemical and physical characteristics
test and test results indicating tree nutrient, and growth health issues
controlling soil and environmental problems
identification of signs and symptoms of tree health problems, including:
disease detection and identification methods
patterns of host–disease interaction for each major disease type
nomenclature of symptoms and signs of pathogens, pests and disorders
describing the nature and severity of disease infection, including:
chronic and acute
passive and aggressive
seasonal and ongoing
localised and unconfined
methods for managing pathogens, pests and disorders, including:
mechanical control practicalities
chemical use, toxicity and safety, compatibility and off-target considerations
managing the cultural factors, growing conditions and environment
managing soil fertility and amelioration
biological control and working with natural agents to control pathogens, pests and growing environment
importance and use of Integrated Pest Management strategies
biosecurity and basic principles of hygiene in arboricultural work
constraints to disease management, including:
timing and scheduling treatments
cost and budgetary constraints
perceived and real value of infected tree
tree diseases collection and diagnosis, including:
collecting, preserving, securing and storing specimens and examples of tree pathogens, pests and disorders
biosecurity risks and mitigation when collecting and storing specimens
preparation of specimens for diagnostics
microscopic and macroscopic examinations
microscope slide preparation
methods of providing a reasoned prognosis
horticultural function, cultural and performance requirements and characteristics of the trees or other woody plants
processes and principles of researching tree health problems, diagnoses and remedial treatment available
industry standards and terminology to describe disease attributes
recording and reporting tree disease prognosis and management strategies, including:
written documentation
oral presentations.
Assessment Conditions
Assessment of the skills in this unit of competency must take place under the following conditions:
physical conditions:
an arboriculture work site with the diseased trees stipulated in the performance evidence
resources, equipment and materials:
computer with word processing software
digital imaging device
diagnostic tools, including sounding hammer, trowel, probe, cordless drill
soil testing equipment and materials
basic dissection microscope 10x – 100x
optical devices, including compound microscope, binoculars, hand lens
sampling equipment, secure storage containers, disinfectant
trees without diseases
trees with biotic diseases
trees with abiotic diseases
bio-secure samples of tree diseases
disinfection materials and equipment to minimise infections
specifications:
codes of practice relevant to tree diagnostics work.
Assessors of this unit must satisfy the requirements for assessors in applicable vocational education and training legislation, frameworks and/or standards. In particular, assessors must 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
Skill | Description |
Reading | Interpret complex and technical information from scientific references to identify diseases and their virulence on host plants |
Writing | Generate complex management plans for diseases, demonstrating control over a range of writing styles |
Sectors
Arboriculture (ARB)