Certified Arborist Test Tree Risk Assessment 2

Question 1

In the ISA Tree Risk Assessment Qualification (TRAQ) framework, what are the three components of tree risk?

Accepted Answer

Probability of failure, target occupancy, and consequence of failure

Answer

Structural defect, site hazards, and occupant vulnerability

Answer

Tree health, environmental factors, and human exposure

Answer

Failure likelihood, branch size, and distance from target

Question 2

What is a 'target' in tree risk assessment terminology, and how does target occupancy affect overall risk rating?

Accepted Answer

People, property, or other valued objects that could be struck if a tree part fails

Answer

A specific defect in the tree structure that the arborist is trying to locate during the assessment

Answer

The geographic point directly beneath the center of mass of a tree being assessed

Answer

The intended pruning cut location that the arborist designates as the assessment endpoint

Question 3

What is 'trunk flare inspection' and what does its absence or deformity potentially indicate?

Accepted Answer

Examination of the base of the trunk to detect buried root flare, girdling roots, or basal decay that indicates structural or root system problems

Answer

A visual inspection of the trunk for fire damage that may have compromised the structural wood

Answer

An assessment of surface root exposure to evaluate erosion risk and tripping hazard

Answer

A measurement of trunk diameter at the widest point to calculate structural capacity

Question 4

What does 'failure mode' refer to in tree risk assessment, and what are the primary structural failure modes assessed?

Accepted Answer

The mechanism by which a tree or tree part fails — including stem failure, branch failure, root failure, and whole tree failure

Answer

The specific pathogen responsible for wood decay causing structural compromise in the tree

Answer

The sequence of events from initial defect discovery to eventual complete tree failure

Answer

The response of the target to the impact of a failing tree part (e.g., property damage vs. personal injury)

Question 5

What is the purpose of resistance drilling in tree risk assessment and what does the instrument measure?

Accepted Answer

It measures the drilling resistance of a small probe as it penetrates the wood, creating a profile that reveals density variations indicating decay, cracks, or voids

Answer

It measures the electrical conductance of trunk wood to detect moisture content changes indicating decay

Answer

It uses sound waves to image the interior of the trunk and produce a tomographic cross-section

Answer

It extracts a small core sample from the trunk that is then laboratory-analyzed for pathogen identification

Question 6

What is the minimum training requirement for an arborist to perform a Level 2 Tree Risk Assessment under ISA TRAQ standards?

Accepted Answer

Completion of the ISA TRAQ training and passing the associated written examination, with ongoing ISA certification maintenance

Answer

Any ISA Certified Arborist with at least 5 years of field experience in tree care

Answer

A state-issued tree hazard assessment license plus ISA Certified Arborist credentials

Answer

A master's degree in arboriculture or urban forestry plus ISA Board Certified Master Arborist credential