CERTIFIED ARBORIST EXAM – MOCK REVISION TEST
QUESTIONS FORM REAL EXAMS LATEST 2025-2026 UPDATE
WITH 150 QUESTIONS & 100% CORRECT DETAILED
ANSWERS GRADED A+ (BRAND NEW!!)
1. Which condition most significantly increases the risk of acute tree failure under wind
loading?
A. High leaf area index
B. Included bark union with acute branch angle
C. Deep, well-drained loam soil
D. High carbohydrate storage in roots
B. Included bark union with acute branch angle
Included bark weakens branch attachment and reduces structural integrity, making failure
under wind stress more likely.
2. What is the primary physiological effect of girdling on a tree?
A. Increased water uptake
B. Disruption of phloem transport
C. Increased photosynthesis
D. Enhanced root expansion
B. Disruption of phloem transport
Girdling blocks phloem, preventing carbohydrate movement from leaves to roots.
3. Which pathogen type is most associated with vascular wilt diseases in trees?
A. Nematodes
B. Fungi and bacteria
C. Viruses only
D. Algae
B. Fungi and bacteria
Vascular wilts such as Verticillium and bacterial wilts colonize xylem tissues.
4. In tree risk assessment, what does “target rating” primarily evaluate?
A. Tree height only
B. Likelihood of pest infestation
C. Potential impact zone if failure occurs
D. Soil nutrient levels
C. Potential impact zone if failure occurs
Target rating assesses what or who could be harmed by tree failure.
5. Which soil condition most limits root respiration?
A. Sandy texture
B. High organic matter
C. Waterlogged anaerobic conditions
D. Slightly acidic pH
C. Waterlogged anaerobic conditions
Oxygen deficiency restricts root respiration and function.
6. Which hormone is most associated with apical dominance in trees?
A. Ethylene
B. Auxin
, C. Cytokinin
D. Abscisic acid
B. Auxin
Auxin produced in shoot tips suppresses lateral bud growth.
7. What is the main purpose of reduction pruning?
A. Remove dead branches only
B. Reduce tree height while maintaining natural form
C. Remove all interior branches
D. Stimulate root growth directly
B. Reduce tree height while maintaining natural form
Reduction pruning shortens branches back to lateral branches.
8. Which condition best describes reaction wood in conifers?
A. Compression wood forms on lower side of leaning stem
B. Tension wood forms on upper side
C. Reaction wood does not form in conifers
D. Only forms in roots
A. Compression wood forms on lower side of leaning stem
Conifers form compression wood to support leaning stems.
9. What is the primary function of mycorrhizal associations?
A. Nitrogen fixation in leaves
B. Enhanced nutrient and water uptake
C. Pest resistance through toxins
D. Photosynthesis enhancement
B. Enhanced nutrient and water uptake
Mycorrhizae improve absorption of phosphorus and other nutrients.
10. Which pruning cut removes a branch back to its point of origin?
A. Heading cut
B. Thinning cut
C. Reduction cut
D. Topping cut
B. Thinning cut
Thinning removes branches at their origin without leaving stubs.
11. Which insect is a known vector of Dutch elm disease?
A. Elm leaf beetle
B. Bark beetles
C. Aphids
D. Caterpillars
B. Bark beetles
Elm bark beetles spread fungal spores between trees.
12. What is the main benefit of deep root fertilization?
A. Eliminates pests
B. Targets nutrients to active root zones
C. Prevents soil compaction
D. Stops fungal growth
B. Targets nutrients to active root zones
Injection places nutrients where absorbing roots are concentrated.
, 13. Which environmental stress most predisposes trees to secondary pest attack?
A. Optimal irrigation
B. Drought stress
C. High nitrogen fertilization
D. Pruning in dormant season
B. Drought stress
Water-stressed trees emit signals and have reduced defenses.
14. What is the primary cause of chlorosis in many urban trees?
A. Excess potassium
B. Iron unavailability in high pH soils
C. Excess sunlight
D. Overwatering roots
B. Iron unavailability in high pH soils
High pH locks iron in unavailable forms causing yellowing.
15. Which structural feature increases wind resistance the most?
A. Narrow crown
B. Dense crown with high sail effect
C. High taper trunk
D. Sparse foliage
A. Narrow crown
A narrow crown reduces wind drag and mechanical stress.
16. What is the primary function of cambium in trees?
A. Water storage
B. Secondary growth production
C. Photosynthesis
D. Nutrient transport in leaves
B. Secondary growth production
Cambium produces xylem and phloem tissues.
17. Which symptom is most indicative of root rot?
A. Leaf scorch only
B. Wilting despite moist soil
C. Increased flowering
D. Thickened bark
B. Wilting despite moist soil
Roots cannot uptake water due to decay.
18. What is the best indicator of structural decay in a tree trunk?
A. Bark color change
B. Presence of fungal fruiting bodies
C. Leaf size increase
D. Soil pH drop
B. Presence of fungal fruiting bodies
Conks or mushrooms often indicate internal decay.
19. Which practice most contributes to soil compaction?
A. Mulching
B. Heavy equipment traffic
C. Drip irrigation
QUESTIONS FORM REAL EXAMS LATEST 2025-2026 UPDATE
WITH 150 QUESTIONS & 100% CORRECT DETAILED
ANSWERS GRADED A+ (BRAND NEW!!)
1. Which condition most significantly increases the risk of acute tree failure under wind
loading?
A. High leaf area index
B. Included bark union with acute branch angle
C. Deep, well-drained loam soil
D. High carbohydrate storage in roots
B. Included bark union with acute branch angle
Included bark weakens branch attachment and reduces structural integrity, making failure
under wind stress more likely.
2. What is the primary physiological effect of girdling on a tree?
A. Increased water uptake
B. Disruption of phloem transport
C. Increased photosynthesis
D. Enhanced root expansion
B. Disruption of phloem transport
Girdling blocks phloem, preventing carbohydrate movement from leaves to roots.
3. Which pathogen type is most associated with vascular wilt diseases in trees?
A. Nematodes
B. Fungi and bacteria
C. Viruses only
D. Algae
B. Fungi and bacteria
Vascular wilts such as Verticillium and bacterial wilts colonize xylem tissues.
4. In tree risk assessment, what does “target rating” primarily evaluate?
A. Tree height only
B. Likelihood of pest infestation
C. Potential impact zone if failure occurs
D. Soil nutrient levels
C. Potential impact zone if failure occurs
Target rating assesses what or who could be harmed by tree failure.
5. Which soil condition most limits root respiration?
A. Sandy texture
B. High organic matter
C. Waterlogged anaerobic conditions
D. Slightly acidic pH
C. Waterlogged anaerobic conditions
Oxygen deficiency restricts root respiration and function.
6. Which hormone is most associated with apical dominance in trees?
A. Ethylene
B. Auxin
, C. Cytokinin
D. Abscisic acid
B. Auxin
Auxin produced in shoot tips suppresses lateral bud growth.
7. What is the main purpose of reduction pruning?
A. Remove dead branches only
B. Reduce tree height while maintaining natural form
C. Remove all interior branches
D. Stimulate root growth directly
B. Reduce tree height while maintaining natural form
Reduction pruning shortens branches back to lateral branches.
8. Which condition best describes reaction wood in conifers?
A. Compression wood forms on lower side of leaning stem
B. Tension wood forms on upper side
C. Reaction wood does not form in conifers
D. Only forms in roots
A. Compression wood forms on lower side of leaning stem
Conifers form compression wood to support leaning stems.
9. What is the primary function of mycorrhizal associations?
A. Nitrogen fixation in leaves
B. Enhanced nutrient and water uptake
C. Pest resistance through toxins
D. Photosynthesis enhancement
B. Enhanced nutrient and water uptake
Mycorrhizae improve absorption of phosphorus and other nutrients.
10. Which pruning cut removes a branch back to its point of origin?
A. Heading cut
B. Thinning cut
C. Reduction cut
D. Topping cut
B. Thinning cut
Thinning removes branches at their origin without leaving stubs.
11. Which insect is a known vector of Dutch elm disease?
A. Elm leaf beetle
B. Bark beetles
C. Aphids
D. Caterpillars
B. Bark beetles
Elm bark beetles spread fungal spores between trees.
12. What is the main benefit of deep root fertilization?
A. Eliminates pests
B. Targets nutrients to active root zones
C. Prevents soil compaction
D. Stops fungal growth
B. Targets nutrients to active root zones
Injection places nutrients where absorbing roots are concentrated.
, 13. Which environmental stress most predisposes trees to secondary pest attack?
A. Optimal irrigation
B. Drought stress
C. High nitrogen fertilization
D. Pruning in dormant season
B. Drought stress
Water-stressed trees emit signals and have reduced defenses.
14. What is the primary cause of chlorosis in many urban trees?
A. Excess potassium
B. Iron unavailability in high pH soils
C. Excess sunlight
D. Overwatering roots
B. Iron unavailability in high pH soils
High pH locks iron in unavailable forms causing yellowing.
15. Which structural feature increases wind resistance the most?
A. Narrow crown
B. Dense crown with high sail effect
C. High taper trunk
D. Sparse foliage
A. Narrow crown
A narrow crown reduces wind drag and mechanical stress.
16. What is the primary function of cambium in trees?
A. Water storage
B. Secondary growth production
C. Photosynthesis
D. Nutrient transport in leaves
B. Secondary growth production
Cambium produces xylem and phloem tissues.
17. Which symptom is most indicative of root rot?
A. Leaf scorch only
B. Wilting despite moist soil
C. Increased flowering
D. Thickened bark
B. Wilting despite moist soil
Roots cannot uptake water due to decay.
18. What is the best indicator of structural decay in a tree trunk?
A. Bark color change
B. Presence of fungal fruiting bodies
C. Leaf size increase
D. Soil pH drop
B. Presence of fungal fruiting bodies
Conks or mushrooms often indicate internal decay.
19. Which practice most contributes to soil compaction?
A. Mulching
B. Heavy equipment traffic
C. Drip irrigation
