ISA Certified Arborist Practice Exam
Questions And Correct Answers (Verified
Answers) Plus Rationales 2026 Q&A
Instant Download Pdf
1. What is the primary function of xylem in trees?
A. Transport sugars
B. Store nutrients
C. Transport water
D. Produce hormones
Answer: C
Rationale: Xylem is responsible for transporting water and dissolved
minerals from roots to leaves.
2. Which soil texture drains the fastest?
A. Clay
B. Silt
C. Loam
D. Sand
Answer: D
Rationale: Sandy soils have large particles and pore spaces, allowing rapid
drainage.
3. What is the ideal pH range for most trees?
A. 3.0–4.0
B. 5.5–7.0
, C. 7.5–9.0
D. 8.0–10.0
Answer: B
Rationale: Most trees thrive in slightly acidic to neutral soils.
4. What process converts light energy into chemical energy in plants?
A. Respiration
B. Transpiration
C. Photosynthesis
D. Fermentation
Answer: C
Rationale: Photosynthesis uses sunlight to produce sugars from carbon
dioxide and water.
5. Which nutrient deficiency commonly causes yellowing between leaf veins?
A. Nitrogen
B. Iron
C. Potassium
D. Calcium
Answer: B
Rationale: Iron deficiency leads to interveinal chlorosis.
6. What is the term for water loss through leaves?
A. Absorption
B. Transpiration
C. Respiration
D. Evaporation
Answer: B
Rationale: Transpiration is the process of water vapor loss from plant
surfaces.
7. Which pruning cut removes a branch entirely?
A. Heading cut
B. Reduction cut
C. Thinning cut
, D. Flush cut
Answer: C
Rationale: Thinning cuts remove entire branches back to their origin.
8. What is the best time to prune most trees?
A. Early spring
B. Late fall
C. Dormant season
D. Mid-summer
Answer: C
Rationale: Dormant pruning reduces stress and disease risk.
9. Which part of a tree produces new cells for growth?
A. Bark
B. Cambium
C. Phloem
D. Heartwood
Answer: B
Rationale: The cambium layer produces new xylem and phloem cells.
10.What is a common symptom of root rot?
A. Leaf curling
B. Wilting despite wet soil
C. Increased flowering
D. Thick bark
Answer: B
Rationale: Root rot prevents water uptake, causing wilting even in moist
soil.
11.Which organism is NOT a common tree pest?
A. Aphids
B. Beetles
C. Fungi
D. Earthworms
Questions And Correct Answers (Verified
Answers) Plus Rationales 2026 Q&A
Instant Download Pdf
1. What is the primary function of xylem in trees?
A. Transport sugars
B. Store nutrients
C. Transport water
D. Produce hormones
Answer: C
Rationale: Xylem is responsible for transporting water and dissolved
minerals from roots to leaves.
2. Which soil texture drains the fastest?
A. Clay
B. Silt
C. Loam
D. Sand
Answer: D
Rationale: Sandy soils have large particles and pore spaces, allowing rapid
drainage.
3. What is the ideal pH range for most trees?
A. 3.0–4.0
B. 5.5–7.0
, C. 7.5–9.0
D. 8.0–10.0
Answer: B
Rationale: Most trees thrive in slightly acidic to neutral soils.
4. What process converts light energy into chemical energy in plants?
A. Respiration
B. Transpiration
C. Photosynthesis
D. Fermentation
Answer: C
Rationale: Photosynthesis uses sunlight to produce sugars from carbon
dioxide and water.
5. Which nutrient deficiency commonly causes yellowing between leaf veins?
A. Nitrogen
B. Iron
C. Potassium
D. Calcium
Answer: B
Rationale: Iron deficiency leads to interveinal chlorosis.
6. What is the term for water loss through leaves?
A. Absorption
B. Transpiration
C. Respiration
D. Evaporation
Answer: B
Rationale: Transpiration is the process of water vapor loss from plant
surfaces.
7. Which pruning cut removes a branch entirely?
A. Heading cut
B. Reduction cut
C. Thinning cut
, D. Flush cut
Answer: C
Rationale: Thinning cuts remove entire branches back to their origin.
8. What is the best time to prune most trees?
A. Early spring
B. Late fall
C. Dormant season
D. Mid-summer
Answer: C
Rationale: Dormant pruning reduces stress and disease risk.
9. Which part of a tree produces new cells for growth?
A. Bark
B. Cambium
C. Phloem
D. Heartwood
Answer: B
Rationale: The cambium layer produces new xylem and phloem cells.
10.What is a common symptom of root rot?
A. Leaf curling
B. Wilting despite wet soil
C. Increased flowering
D. Thick bark
Answer: B
Rationale: Root rot prevents water uptake, causing wilting even in moist
soil.
11.Which organism is NOT a common tree pest?
A. Aphids
B. Beetles
C. Fungi
D. Earthworms
