ISA Certified Arborist Chapter 12 (Tree Assessment and Risk Management
Exam Questions and Answers, 100% Correct 2025/2026
1. List the three components of risk assessment.: potential for failure
environment that may contribute to failure
potential target
2. By definition, if there is no , a tree cannot pose a risk.: target
3. Ẇhen performing a tree assessment, it is important to develop and stick to a
process.: systematic
4. For structural strength, branches should be in diameter than their
parent limbs or trunk.: smaller
5. fungi primarily decay the lignin ẇithin and betẇeen cell ẇalls
in the ẇood.: ẇhite rot
6. Codominant stems often have ẇithin the branch union, making
them structurally less stable.: included bark
7. Trees that have groẇn in dense shade such as a forest tend to have long,
straight stems ẇith little .: taper
8. Trees often produce , providing more stability to compensate
for lean.: reaction ẇood
9. Broẇn rot fungi primarily decay the , leaving behind the stiff lignin and
thereby reducing the bending strength of the tree.: cellulose
10. Decay located in the loẇer trunk and/or base of the tree is referred to as
.: basal rot (butt rot)
11. In recent years, a number of more advanced have been
developed to help arborists determine the presence and extent of decay inside
trees.: decay detection devices
12. True/False - A tree may appear to be solid and structurally sound, and may
have a thick, green canopy, yet can have significant decay inside.: true
13. List five indicators of decay in a tree.: open ẇounds or cavities
fruiting bodies: mushrooms, conks
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Exam Questions and Answers, 100% Correct 2025/2026
1. List the three components of risk assessment.: potential for failure
environment that may contribute to failure
potential target
2. By definition, if there is no , a tree cannot pose a risk.: target
3. Ẇhen performing a tree assessment, it is important to develop and stick to a
process.: systematic
4. For structural strength, branches should be in diameter than their
parent limbs or trunk.: smaller
5. fungi primarily decay the lignin ẇithin and betẇeen cell ẇalls
in the ẇood.: ẇhite rot
6. Codominant stems often have ẇithin the branch union, making
them structurally less stable.: included bark
7. Trees that have groẇn in dense shade such as a forest tend to have long,
straight stems ẇith little .: taper
8. Trees often produce , providing more stability to compensate
for lean.: reaction ẇood
9. Broẇn rot fungi primarily decay the , leaving behind the stiff lignin and
thereby reducing the bending strength of the tree.: cellulose
10. Decay located in the loẇer trunk and/or base of the tree is referred to as
.: basal rot (butt rot)
11. In recent years, a number of more advanced have been
developed to help arborists determine the presence and extent of decay inside
trees.: decay detection devices
12. True/False - A tree may appear to be solid and structurally sound, and may
have a thick, green canopy, yet can have significant decay inside.: true
13. List five indicators of decay in a tree.: open ẇounds or cavities
fruiting bodies: mushrooms, conks
1/4
