CTSP Risk Assessment 4 — Questions and Answers
Question 1: Which advanced diagnostic tool uses sound wave pulses to create a cross-sectional map of wood density inside a trunk?
- Resistograph
- Sonic/acoustic tomography (Correct answer)
- Increment borer
- Chlorophyll meter
Correct answer: Sonic/acoustic tomography
Sonic tomography sends sound pulses between sensors placed around the trunk to map internal wood density and detect decay.
Question 2: A CTSP finds that a tree's root plate has lifted on one side after recent wind events. What does this indicate?
- The tree is responding to excess moisture
- The root system has been compromised and failure risk is elevated (Correct answer)
- Normal wind-induced trunk movement
- The tree is establishing new anchor roots
Correct answer: The root system has been compromised and failure risk is elevated
A lifted root plate indicates the tree's anchoring roots have failed or been damaged, significantly increasing overturn risk.
Question 3: Under the ISA's three-level assessment system, which level is appropriate when a Level 1 walkby reveals a potential problem?
- Another Level 1 by a different inspector
- Level 2 – Basic Assessment (Correct answer)
- Level 3 – Advanced Assessment immediately
- A utility line clearance audit
Correct answer: Level 2 – Basic Assessment
A Level 2 Basic Assessment is the appropriate follow-up when a Level 1 walkby identifies a concern requiring closer examination.
Question 4: Which of the following soil conditions most increases the risk of wind-throw for a large tree?
- Well-drained sandy loam
- Shallow, compacted, or saturated soil limiting root depth (Correct answer)
- Deep clay soil with high organic content
- Soil recently amended with compost
Correct answer: Shallow, compacted, or saturated soil limiting root depth
Shallow, compacted, or saturated soils prevent deep root anchorage, greatly increasing vulnerability to wind-throw.
Question 5: A CTSP is evaluating a tree with significant trunk lean. Which measurement helps determine if the lean is a structural concern?
- Diameter at breast height (DBH)
- The degree of lean relative to trunk diameter and root depth (Correct answer)
- The height of the lowest live branch
- Annual ring count from an increment core
Correct answer: The degree of lean relative to trunk diameter and root depth
Lean severity is assessed relative to trunk size and the root system's capacity to counteract the off-center load.
Question 6: What is 'failure zone' in the context of a tree risk assessment?
- The area where pruning cuts are most likely to cause decay
- The area that would be struck if a specific tree part fails (Correct answer)
- The region of the canopy showing dieback
- The buffer zone around pesticide application areas
Correct answer: The area that would be struck if a specific tree part fails
The failure zone is the area on the ground that would be impacted if a specific tree part (branch, stem, or whole tree) were to fail.
Question 7: A crown asymmetry caused by a nearby structure blocking sunlight is observed on a mature maple. What is the primary risk concern?
- Increased photosynthesis on the exposed side
- Uneven weight distribution creating lateral loading and lean risk (Correct answer)
- Improved air circulation through the canopy
- Enhanced root growth toward the structure
Correct answer: Uneven weight distribution creating lateral loading and lean risk
Asymmetric crowns create unbalanced lateral loads, increasing stress on the root system and raising lean and failure risk.
CTSP Risk Assessment 4
Which advanced diagnostic tool uses sound wave pulses to create a cross-sectional map of wood density inside a trunk?