ISA ARBORIST FINAL EXAM STUDY GUIDE
2026/2027 COMPLETE QUESTIONS WITH
VERIFIED CORRECT ANSWERS ||
100% GUARANTEED PASS
<NEWEST VERSION>
1. Chlorophyll - ANSWER ✔ Makes the color or the leaves green so
photosynthesis can take place
2. Transpiration - ANSWER ✔ loss of water vapor from leaves
3. Bark - ANSWER ✔ protects branches & trunk of tree from injury
4. Excurrent Growth - ANSWER ✔ Orientation of growth in external cell
5. M.A.D.HORSE - ANSWER ✔ Opposite leaf arrangement
MAPLE
ASH
DOGWOOD
HORSECHESTNUT
6. pH - ANSWER ✔ Measure of acidity or alkaline from 0 to 14
<7 acidic 7> Alkaline
7 Neutral
,7. Decurrent Growth - ANSWER ✔ rounded or broader tree growth
8. Field Capacity - ANSWER ✔ soil after gravitational water has drained
9. Buffering Capacity - ANSWER ✔ ability to maintain pH
10.Gravitational Water - ANSWER ✔ water that drains from the macropores
11.Meristems - ANSWER ✔ part of the root that gets it get bigger
12.Micropores - ANSWER ✔ tend to be water filled soil particles
13.Clay - ANSWER ✔ fine textured soil particles; greater water holding
capability
14.Control of growth - ANSWER ✔ genetic potentials & environmental
surroundings
15.Root Pruning - ANSWER ✔ pre-digging to create a more densely rooted
ball
16.The ideal soil ratio for solids to pore space is:
(A) 20:80 (B) 35:65 (C) 40:60 (D) 50:50 - ANSWER ✔ D
17.What is the correct scientific name for the oak tree genus?
(A) Quercus (B) Pyrus (C) Larix (D) Acer - ANSWER ✔ A
,18.Which of the following is not one of the five major categories of soil
horizons?
(A) O (B) E (C) N (D) B - ANSWER ✔ C
19.Loam is least composed of what soil classification?
(A) Sand(B) Silt(C) Clay(D) Loam is composed of all soils evenly -
ANSWER ✔ C
20.What is the difference in magnitude of acidity between a PH level reading of
4 vs. a PH reading of 7?
1(B) 3(C) 100 (D) 1000 - ANSWER ✔ D
21.What tree symptom is not likely to be caused by insect infestation?
(A) Leaf droop
(B) Yellow specks
(C) Off-color foliage
(D) Leaves with a scorched appearance - ANSWER ✔ D
22.What insect listed below is classified as having piercing or sucking
mouthparts?
(A) Leafhoppers
(B) Beetles
(C) Weevils
(D) Borers - ANSWER ✔ A
23.What herbicide type eliminates the whole of the plant over a short period of
time?
(A) Pre-emergent
(B) Contact
(C) Systemic
, (D) Drench - ANSWER ✔ C
24.If a tree is suffering from girdling root, what is most likely not an advisable
action?
(A) Remove the largest roots first
(B) Remove only the smallest roots
(C) Remove the tree
(D) None of the above - ANSWER ✔ A
25.Which of the following is not classified as an insect?
(A) Mites
(B) Beetles
(C) Moths
(D) Caterpillars - ANSWER ✔ A
26.What statement below is false regarding vascular disease?
(A) Examples include Dutch elm disease and oak wilt
(B) It is treatable if found in a reasonable timeframe
(C) It affects the flow of water and nutrients
(D) It originates from pathogens entering the plant - ANSWER ✔ B
27.Cellulose and lignin are a defense mechanism against predators by what
means?
(A) They give off an unfavorable odor
(B) They can't be digested
(C) They have a poor taste
(D) They are toxic - ANSWER ✔ B
28.A tree exhibits wounded areas of the lower trunk and some physical damage
to surface roots. What is the most likely cause of the injury?
(A) Frost
2026/2027 COMPLETE QUESTIONS WITH
VERIFIED CORRECT ANSWERS ||
100% GUARANTEED PASS
<NEWEST VERSION>
1. Chlorophyll - ANSWER ✔ Makes the color or the leaves green so
photosynthesis can take place
2. Transpiration - ANSWER ✔ loss of water vapor from leaves
3. Bark - ANSWER ✔ protects branches & trunk of tree from injury
4. Excurrent Growth - ANSWER ✔ Orientation of growth in external cell
5. M.A.D.HORSE - ANSWER ✔ Opposite leaf arrangement
MAPLE
ASH
DOGWOOD
HORSECHESTNUT
6. pH - ANSWER ✔ Measure of acidity or alkaline from 0 to 14
<7 acidic 7> Alkaline
7 Neutral
,7. Decurrent Growth - ANSWER ✔ rounded or broader tree growth
8. Field Capacity - ANSWER ✔ soil after gravitational water has drained
9. Buffering Capacity - ANSWER ✔ ability to maintain pH
10.Gravitational Water - ANSWER ✔ water that drains from the macropores
11.Meristems - ANSWER ✔ part of the root that gets it get bigger
12.Micropores - ANSWER ✔ tend to be water filled soil particles
13.Clay - ANSWER ✔ fine textured soil particles; greater water holding
capability
14.Control of growth - ANSWER ✔ genetic potentials & environmental
surroundings
15.Root Pruning - ANSWER ✔ pre-digging to create a more densely rooted
ball
16.The ideal soil ratio for solids to pore space is:
(A) 20:80 (B) 35:65 (C) 40:60 (D) 50:50 - ANSWER ✔ D
17.What is the correct scientific name for the oak tree genus?
(A) Quercus (B) Pyrus (C) Larix (D) Acer - ANSWER ✔ A
,18.Which of the following is not one of the five major categories of soil
horizons?
(A) O (B) E (C) N (D) B - ANSWER ✔ C
19.Loam is least composed of what soil classification?
(A) Sand(B) Silt(C) Clay(D) Loam is composed of all soils evenly -
ANSWER ✔ C
20.What is the difference in magnitude of acidity between a PH level reading of
4 vs. a PH reading of 7?
1(B) 3(C) 100 (D) 1000 - ANSWER ✔ D
21.What tree symptom is not likely to be caused by insect infestation?
(A) Leaf droop
(B) Yellow specks
(C) Off-color foliage
(D) Leaves with a scorched appearance - ANSWER ✔ D
22.What insect listed below is classified as having piercing or sucking
mouthparts?
(A) Leafhoppers
(B) Beetles
(C) Weevils
(D) Borers - ANSWER ✔ A
23.What herbicide type eliminates the whole of the plant over a short period of
time?
(A) Pre-emergent
(B) Contact
(C) Systemic
, (D) Drench - ANSWER ✔ C
24.If a tree is suffering from girdling root, what is most likely not an advisable
action?
(A) Remove the largest roots first
(B) Remove only the smallest roots
(C) Remove the tree
(D) None of the above - ANSWER ✔ A
25.Which of the following is not classified as an insect?
(A) Mites
(B) Beetles
(C) Moths
(D) Caterpillars - ANSWER ✔ A
26.What statement below is false regarding vascular disease?
(A) Examples include Dutch elm disease and oak wilt
(B) It is treatable if found in a reasonable timeframe
(C) It affects the flow of water and nutrients
(D) It originates from pathogens entering the plant - ANSWER ✔ B
27.Cellulose and lignin are a defense mechanism against predators by what
means?
(A) They give off an unfavorable odor
(B) They can't be digested
(C) They have a poor taste
(D) They are toxic - ANSWER ✔ B
28.A tree exhibits wounded areas of the lower trunk and some physical damage
to surface roots. What is the most likely cause of the injury?
(A) Frost
