ISA ARBORIST EXAM SCRIPT 191 2026
QUESTIONS WITH SOLUTIONS GRADED A+
◉ What are the major water-conducting cells in angiosperms?
Answer: Vessels.
◉ When does carbon sequestration occur? Answer: During
photosynthesis.
◉ What do Armillaria mushrooms indicate? Answer: Root decay.
◉ What is a poor tree quality for a shaded nature walk? Answer:
Abundant fruiting.
◉ What is a spring pole? Answer: A pinned branch or small tree
under tension by fallen trees.
◉ How is the branch collar formed? Answer: By the annual process
by which tissue is layered where the branch and stem meet.
◉ Why should temporary branches be left on a young tree? Answer:
They contribute to proper taper development.
,◉ What pruning system starts with heading cuts followed by sprout
removal? Answer: Pollarding.
◉ What does a significant number of small fruiting bodies along a
branch indicate? Answer: Sapwood rot.
◉ What is the escape path direction when felling a tree? Answer: At
a 45-degree angle, away from the direction of fall.
◉ Which recommendation is not for supporting a healthy
landscape? Answer: Pre-treating with a broad-spectrum pesticide
before mulching.
◉ What are the cork cambium and external layer of bark collectively
called? Answer: Periderm.
◉ Which is not a deciduous conifer? Answer: Deodar cedar (Cedrus
deodara).
◉ How should brush chippers be fed? Answer: The butt end of the
branch first.
◉ Why is it beneficial to maintain large, mature trees? Answer:
Large trees provide more benefits than small trees.
, ◉ Which soil aggregate structure type has slow water drainage
issues? Answer: Platy.
◉ What is the term for applying compost to soil over turf? Answer:
Topdressing.
◉ What happens if a leaf is missing its cuticle? Answer: It would
shrivel, due to desiccation.
◉ What cut decreases the length of a larger branch back to a smaller
branch? Answer: Reduction cut.
◉ What is considered an ideal soil texture? Answer: Loam.
◉ What is best practice in PHC when treating a tree? Answer: Factor
in the surrounding environment.
◉ What is true about random sampling, partial, and complete tree
inventories? Answer: Complete inventories are the most expensive,
but provide information on all trees.
◉ What is true about the three components of soil? Answer:
Physical, chemical, and biological properties influence each other.
QUESTIONS WITH SOLUTIONS GRADED A+
◉ What are the major water-conducting cells in angiosperms?
Answer: Vessels.
◉ When does carbon sequestration occur? Answer: During
photosynthesis.
◉ What do Armillaria mushrooms indicate? Answer: Root decay.
◉ What is a poor tree quality for a shaded nature walk? Answer:
Abundant fruiting.
◉ What is a spring pole? Answer: A pinned branch or small tree
under tension by fallen trees.
◉ How is the branch collar formed? Answer: By the annual process
by which tissue is layered where the branch and stem meet.
◉ Why should temporary branches be left on a young tree? Answer:
They contribute to proper taper development.
,◉ What pruning system starts with heading cuts followed by sprout
removal? Answer: Pollarding.
◉ What does a significant number of small fruiting bodies along a
branch indicate? Answer: Sapwood rot.
◉ What is the escape path direction when felling a tree? Answer: At
a 45-degree angle, away from the direction of fall.
◉ Which recommendation is not for supporting a healthy
landscape? Answer: Pre-treating with a broad-spectrum pesticide
before mulching.
◉ What are the cork cambium and external layer of bark collectively
called? Answer: Periderm.
◉ Which is not a deciduous conifer? Answer: Deodar cedar (Cedrus
deodara).
◉ How should brush chippers be fed? Answer: The butt end of the
branch first.
◉ Why is it beneficial to maintain large, mature trees? Answer:
Large trees provide more benefits than small trees.
, ◉ Which soil aggregate structure type has slow water drainage
issues? Answer: Platy.
◉ What is the term for applying compost to soil over turf? Answer:
Topdressing.
◉ What happens if a leaf is missing its cuticle? Answer: It would
shrivel, due to desiccation.
◉ What cut decreases the length of a larger branch back to a smaller
branch? Answer: Reduction cut.
◉ What is considered an ideal soil texture? Answer: Loam.
◉ What is best practice in PHC when treating a tree? Answer: Factor
in the surrounding environment.
◉ What is true about random sampling, partial, and complete tree
inventories? Answer: Complete inventories are the most expensive,
but provide information on all trees.
◉ What is true about the three components of soil? Answer:
Physical, chemical, and biological properties influence each other.
