CATS Urban Tree Risk Assessment & Mitigation 4

Question 1

Which ISA risk assessment term describes the zone within which a target could be struck if a tree part were to fail?

Accepted Answer

Target zone

Answer

The 'target zone' is the area where people, property, or other valued assets could be struck by a failing tree part.

Question 2

What is the primary purpose of performing a 'quantified' risk assessment rather than a basic or advanced assessment?

Accepted Answer

To assign numerical probability values for communication and legal purposes

Answer

Quantified assessments assign numerical probabilities to failure and consequence events, making risk communication precise for legal, insurance, or management purposes.

Question 3

A crack that runs parallel to the grain on opposite sides of a trunk, 180 degrees apart, is most indicative of:

Accepted Answer

Radial shake or wind shake

Answer

Radial shake involves longitudinal cracks along the grain that can appear on opposite faces of the trunk, often associated with wind stress or growth stresses.

Question 4

Canopy dieback progressing from branch tips inward toward the trunk most likely indicates:

Accepted Answer

Root or vascular dysfunction limiting water supply

Answer

Tip dieback progressing toward the trunk (top-down or outside-in) is a classic symptom of root disease, vascular wilt, or severe root damage limiting water transport.

Question 5

Which mitigation option is most appropriate when a significant defect cannot be adequately addressed by pruning or cabling?

Accepted Answer

Tree removal

Answer

When structural defects pose unacceptable risk and cannot be sufficiently mitigated by other means, tree removal is the appropriate and responsible action.

(CATS) Certified Arborist Tree Service of Albuquerque Practice Test

(CATS) Certified Arborist Tree Service of Albuquerque Practice Test

CATS Urban Tree Risk Assessment & Mitigation 4