CTSP Hazard and Risk Assessment 4 — Questions and Answers
Question 1: A tree assessment reveals a large crack running vertically through the trunk. Which term describes this condition?
- Frost crack only
- Shear crack with potential for rapid failure (Correct answer)
- Radial shake unrelated to load
- Compression failure on the tension side
Correct answer: Shear crack with potential for rapid failure
A vertical crack through the trunk can indicate a shear crack caused by torsional or bending loads and presents a significant failure risk.
Question 2: Which assessment interval is generally recommended for trees rated as 'high risk' with mitigation deferred?
- Every five years
- Annually or more frequently (Correct answer)
- Every three years
- Only after a major storm event
Correct answer: Annually or more frequently
High-risk trees with deferred mitigation should be reassessed annually or more frequently because conditions can deteriorate rapidly.
Question 3: What is the significance of the 'failure zone' in tree risk assessment site planning?
- The area where tree debris is piled after pruning
- The area that would be struck if the tree or a part failed (Correct answer)
- The zone of soil compaction under the root plate
- The buffer area required around a climbing anchor point
Correct answer: The area that would be struck if the tree or a part failed
The failure zone is the area that would be impacted by falling tree parts, and it is used to identify whether targets are at risk.
Question 4: During a post-storm assessment, an arborist finds a tree with a partially detached branch hanging in the canopy. This condition is commonly called:
- Deadwood
- A widow maker or hangar (Correct answer)
- A basal sprout cluster
- A co-dominant stem failure
Correct answer: A widow maker or hangar
A partially detached or suspended branch caught in the canopy is called a widow maker or hangar and poses an immediate hazard to workers below.
Question 5: Which tree defect is characterized by a sudden, unpredictable failure of large branches during calm, hot weather in summer?
- Frost crack
- Summer branch drop (sudden branch drop) (Correct answer)
- Compression wood failure
- Included bark splitting
Correct answer: Summer branch drop (sudden branch drop)
Summer branch drop is a poorly understood phenomenon where large limbs fail without warning during hot, dry, calm conditions.
Question 6: A city arborist must assess hundreds of street trees efficiently. Which approach provides the best balance of thoroughness and efficiency for initial screening?
- Full advanced-level assessment of every tree
- Basic level visual assessment to prioritize trees needing further review (Correct answer)
- Hiring a non-certified crew to photograph all trees
- Waiting for public complaints before inspecting
Correct answer: Basic level visual assessment to prioritize trees needing further review
A basic-level visual assessment efficiently screens the inventory to identify trees requiring advanced assessment, optimizing resource allocation.
Question 7: Which factor most significantly reduces the effectiveness of visual tree assessment for detecting structural problems?
- Assessing during leaf-out in spring
- Dense ivy or vine growth obscuring the trunk and base (Correct answer)
- Bright sunlight during midday inspection
- Presence of epiphytic mosses on bark
Correct answer: Dense ivy or vine growth obscuring the trunk and base
Dense ivy or vine growth can hide decay, cracks, cavities, and other structural defects, making a reliable visual assessment impossible.
CTSP Hazard and Risk Assessment 4
A tree assessment reveals a large crack running vertically through the trunk.
Which term describes this condition?