ISA Certified Arborist Exam With Actual
Questions & Verified Answers, Plus
Explained Rationales/Expert Verified
For Guaranteed 100% Pass 2026/Latest
Update/Instant Download Pdf
1. Which soil texture holds the greatest amount of water?
A. Sand
B. Silt
C. Loam
D. Clay
Answer: D. Clay
Clay particles are very small and have high surface area,
allowing them to retain more water than other soil types.
2. The primary function of tree roots is to:
A. Produce food
B. Store oxygen
C. Absorb water and nutrients
D. Provide shade
Answer: C. Absorb water and nutrients
Roots anchor the tree and absorb water and mineral nutrients
necessary for growth.
3. Which pruning cut removes a branch back to its point of origin?
A. Reduction cut
B. Heading cut
, C. Topping cut
D. Removal cut
Answer: D. Removal cut
A removal cut eliminates a branch entirely at its point of
attachment.
4. The branch collar is important because it:
A. Strengthens the branch
B. Contains decay-resistant tissue
C. Produces new shoots
D. Prevents insect infestation
Answer: B. Contains decay-resistant tissue
The branch collar helps compartmentalize wounds and limits
decay spread.
5. Which condition results from improper mulching against the
trunk?
A. Sunscald
B. Root flare exposure
C. Girdling roots
D. Increased photosynthesis
Answer: C. Girdling roots
Excessive mulch against the trunk encourages roots to circle and
girdle the stem.
6. Codominant stems are a concern because they:
A. Increase shade tolerance
B. Have weak branch attachments
C. Improve tree symmetry
D. Reduce wind resistance
Answer: B. Have weak branch attachments
, Codominant stems often form included bark, leading to
structural weakness.
7. The process by which trees produce food is:
A. Respiration
B. Transpiration
C. Photosynthesis
D. Germination
Answer: C. Photosynthesis
Photosynthesis converts sunlight, carbon dioxide, and water into
sugars.
8. Which nutrient is most responsible for leaf growth?
A. Potassium
B. Nitrogen
C. Phosphorus
D. Calcium
Answer: B. Nitrogen
Nitrogen is essential for chlorophyll production and vegetative
growth.
9. A tree that sheds leaves seasonally is classified as:
A. Evergreen
B. Coniferous
C. Deciduous
D. Perennial
Answer: C. Deciduous
Deciduous trees lose their leaves annually, usually in autumn.
10. The outer protective layer of a tree trunk is the:
A. Cambium
B. Xylem
C. Phloem
Questions & Verified Answers, Plus
Explained Rationales/Expert Verified
For Guaranteed 100% Pass 2026/Latest
Update/Instant Download Pdf
1. Which soil texture holds the greatest amount of water?
A. Sand
B. Silt
C. Loam
D. Clay
Answer: D. Clay
Clay particles are very small and have high surface area,
allowing them to retain more water than other soil types.
2. The primary function of tree roots is to:
A. Produce food
B. Store oxygen
C. Absorb water and nutrients
D. Provide shade
Answer: C. Absorb water and nutrients
Roots anchor the tree and absorb water and mineral nutrients
necessary for growth.
3. Which pruning cut removes a branch back to its point of origin?
A. Reduction cut
B. Heading cut
, C. Topping cut
D. Removal cut
Answer: D. Removal cut
A removal cut eliminates a branch entirely at its point of
attachment.
4. The branch collar is important because it:
A. Strengthens the branch
B. Contains decay-resistant tissue
C. Produces new shoots
D. Prevents insect infestation
Answer: B. Contains decay-resistant tissue
The branch collar helps compartmentalize wounds and limits
decay spread.
5. Which condition results from improper mulching against the
trunk?
A. Sunscald
B. Root flare exposure
C. Girdling roots
D. Increased photosynthesis
Answer: C. Girdling roots
Excessive mulch against the trunk encourages roots to circle and
girdle the stem.
6. Codominant stems are a concern because they:
A. Increase shade tolerance
B. Have weak branch attachments
C. Improve tree symmetry
D. Reduce wind resistance
Answer: B. Have weak branch attachments
, Codominant stems often form included bark, leading to
structural weakness.
7. The process by which trees produce food is:
A. Respiration
B. Transpiration
C. Photosynthesis
D. Germination
Answer: C. Photosynthesis
Photosynthesis converts sunlight, carbon dioxide, and water into
sugars.
8. Which nutrient is most responsible for leaf growth?
A. Potassium
B. Nitrogen
C. Phosphorus
D. Calcium
Answer: B. Nitrogen
Nitrogen is essential for chlorophyll production and vegetative
growth.
9. A tree that sheds leaves seasonally is classified as:
A. Evergreen
B. Coniferous
C. Deciduous
D. Perennial
Answer: C. Deciduous
Deciduous trees lose their leaves annually, usually in autumn.
10. The outer protective layer of a tree trunk is the:
A. Cambium
B. Xylem
C. Phloem
