ISA Exam (Arborist Certification) PREP
QUESTIONS With Actual Answers 2026-
2027 Edition.
Compacted soil often lacks which factor necessary for plant survival? - Answer Sufficient
water, oxygen, and pore space
If a transplanted tree declines or dies within the first year, the cause is most likely a lack or
excess of _______ - Answer Water
What type of injury occurs when the outer wood and bark of a tree cool rapidly, causing both to
contract and split? - Answer Frost cracks
A root that arises from a stem, rather than from another root, is called a(n) _______. - Answer
Adventitious root
In an area around a tree that is frequently mowed, an arborist removed the turf grass and
replaced it with mulch. What type of problem was she trying to prevent? - Answer Physical
damage
Leaf or fruit drop is also called _______. - Answer Abscission
What type of plant is more adapted to dry areas? - Answer Xerophyte
What is the point at which a plant cannot pull any more water from the soil and suffers
permanent damage? - Answer Permanent wilting point
Which of the following is a physical injury? - Answer Lightning damage
Which of the following situations is prone to girdling roots? - Answer Trees planted too deeply
The process in which a tree uses oxygen to convert carbohydrates into energy is called _______.
- Answer Aerobic respiration
A prolonged water shortage lasting from days to months refers to what is called _______. -
Answer Chronic water deficit
,What is the most common growth factor that trees or other plants compete for? - Answer
Sunlight
A plant is more likely to experience freezing and chilling injury if it has not had the chance to
become _______. - Answer Hardened off
A compound that is poisonous to plants is considered _______. - Answer Phytotoxic
A tree's natural process of defense by which chemical and physical boundaries are created to
limit the spread of disease and decay organisms is known as _______. - Answer
Compartmentalization
What is the transition zone from trunk to roots? - Answer Trunk Flare
A tree has a long, spirally oriented scar down the length of its trunk that follows the grain of the
wood where the bark was ripped away. What was the likely cause of this injury? - Answer
Lightning Strike
A substance that moves throughout an entire plant is said to be _______. - Answer systemic
The signs of insect feeding damage are directly related to ________. - Answer The type of
mouthparts the insect has
Aphids/adelgids, some scales, leafhoppers, and true bugs use what method of feeding? -
Answer Piercing and sucking
What is honeydew? - Answer a sticky substance secreted by certain insects when feeding
upon plants
Japanese beetles create skeletonized leaves. How are Japanese beetles classified? - Answer
Defoliating insects
Scale insects are sometimes confused with galls. What is a quick way to distinguish between the
two? - Answer Scrape of the bump and observe the bark below
Insects that carry and transmit disease are known as _______. - Answer Vectors
Fungicides are usually most effective when used to _______. - Answer Prevent the
etablishment of a disease
,Which of the following is a conclusive sign of borer damage? - Answer Small holes in the trunk
and branches with frass
Animals can create risk situations for arborist work in trees. - Answer True
Which of the following is characteristic of a vascular disease? - Answer extremely difficult to
eliminate after infection occurs
What is a common leaf symptom of feeding damage by piercing and sucking insects? - Answer
Chlorosis, stippling, drooping
Nematodes most commonly attack what part of the tree? - Answer Root system
Which of the following types of scales produces honeydew? - Answer Soft Scales
Which of the following is a way beavers can cause tree damage? - Answer Feeding on a tree's
bark, submerging roots for long periods of time by damming waterways, felling trees for dam
construction
Some diseases require more than one host to complete their life cycle. These hosts are called
_______. - Answer Alternate host
Which animal has a feeding pattern that looks jagged or torn? - Answer Deer
What can become serious if a susceptible host, a pathogenic organism, a suitable environment,
and the right timing are present? - Answer Disease
If rodents are a problem during the winter, you should _______. - Answer Place a physical
barrier around the affected tree
A small, often microscopic, wormlike creature is called a(n) _______. - Answer Nematode
An important part of limb walking that helps maintain balance without putting excessive weight
on the tree is to _______. - Answer Keep your weight on the rope
Climbing spurs should be used only when working on trees _______. - Answer to be removed
where no electrical hazards exists
, A Prusik loop is used in climbing _______. - Answer to tie in for the secured footlock technique
When using a chain saw in a tree, a climber must _______. - Answer be secured with 2
separate lines such as a work-positioning lanyard and a climbing line, 2 climbing lines, or 2
lanyards
According to the ANSI Z133 safety standards, climbing lines must _________. - Answer have a
minimum tensile strength of at least 24.04 kN
The technique in which a climber ascends a tree by placing his or her feet high on the trunk and
thrusts the hips upward while pulling the slack out of the climbing line and advancing the
friction hitch is called _______ - Answer Body thrusting
Knots that tie two ropes together are known as_______. - Answer Bends
Which of the following statements about tree inspection and pre-climb inspection is true? -
Answer Before climbing a tree, the climber should check for hazards.
The recommended method for tying in is to pass the climbing line _______. - Answer Around a
leader and over a lateral
A technique in which a climber ties in on a second limb (or second tree) with the opposite end
of the climbing line or a second climbing line is called _______. - Answer Double crotching
If a pole pruner or a pole saw is used in a tree, _______. - Answer it should be hung in such a
way that the sharp edge is away from the worker and such that it cannot be accidentally
dislodged
When performing a pre-climb tree inspection, you should look for _________. - Answer
electrical conductors, stinging insects or other animal hazards, dead or broken limbs, decay,
cracks or other tree defects
If a victim appears to have a broken neck or spinal injury, and is breathing, what should you do?
- Answer Do not move the victim. make sure the victim is secure and his or her equipment is
secure, and wait for emergency help to arrive
A thin line with a throw weight/bag attached used to install a line in a tree is called a _______. -
Answer throwline
QUESTIONS With Actual Answers 2026-
2027 Edition.
Compacted soil often lacks which factor necessary for plant survival? - Answer Sufficient
water, oxygen, and pore space
If a transplanted tree declines or dies within the first year, the cause is most likely a lack or
excess of _______ - Answer Water
What type of injury occurs when the outer wood and bark of a tree cool rapidly, causing both to
contract and split? - Answer Frost cracks
A root that arises from a stem, rather than from another root, is called a(n) _______. - Answer
Adventitious root
In an area around a tree that is frequently mowed, an arborist removed the turf grass and
replaced it with mulch. What type of problem was she trying to prevent? - Answer Physical
damage
Leaf or fruit drop is also called _______. - Answer Abscission
What type of plant is more adapted to dry areas? - Answer Xerophyte
What is the point at which a plant cannot pull any more water from the soil and suffers
permanent damage? - Answer Permanent wilting point
Which of the following is a physical injury? - Answer Lightning damage
Which of the following situations is prone to girdling roots? - Answer Trees planted too deeply
The process in which a tree uses oxygen to convert carbohydrates into energy is called _______.
- Answer Aerobic respiration
A prolonged water shortage lasting from days to months refers to what is called _______. -
Answer Chronic water deficit
,What is the most common growth factor that trees or other plants compete for? - Answer
Sunlight
A plant is more likely to experience freezing and chilling injury if it has not had the chance to
become _______. - Answer Hardened off
A compound that is poisonous to plants is considered _______. - Answer Phytotoxic
A tree's natural process of defense by which chemical and physical boundaries are created to
limit the spread of disease and decay organisms is known as _______. - Answer
Compartmentalization
What is the transition zone from trunk to roots? - Answer Trunk Flare
A tree has a long, spirally oriented scar down the length of its trunk that follows the grain of the
wood where the bark was ripped away. What was the likely cause of this injury? - Answer
Lightning Strike
A substance that moves throughout an entire plant is said to be _______. - Answer systemic
The signs of insect feeding damage are directly related to ________. - Answer The type of
mouthparts the insect has
Aphids/adelgids, some scales, leafhoppers, and true bugs use what method of feeding? -
Answer Piercing and sucking
What is honeydew? - Answer a sticky substance secreted by certain insects when feeding
upon plants
Japanese beetles create skeletonized leaves. How are Japanese beetles classified? - Answer
Defoliating insects
Scale insects are sometimes confused with galls. What is a quick way to distinguish between the
two? - Answer Scrape of the bump and observe the bark below
Insects that carry and transmit disease are known as _______. - Answer Vectors
Fungicides are usually most effective when used to _______. - Answer Prevent the
etablishment of a disease
,Which of the following is a conclusive sign of borer damage? - Answer Small holes in the trunk
and branches with frass
Animals can create risk situations for arborist work in trees. - Answer True
Which of the following is characteristic of a vascular disease? - Answer extremely difficult to
eliminate after infection occurs
What is a common leaf symptom of feeding damage by piercing and sucking insects? - Answer
Chlorosis, stippling, drooping
Nematodes most commonly attack what part of the tree? - Answer Root system
Which of the following types of scales produces honeydew? - Answer Soft Scales
Which of the following is a way beavers can cause tree damage? - Answer Feeding on a tree's
bark, submerging roots for long periods of time by damming waterways, felling trees for dam
construction
Some diseases require more than one host to complete their life cycle. These hosts are called
_______. - Answer Alternate host
Which animal has a feeding pattern that looks jagged or torn? - Answer Deer
What can become serious if a susceptible host, a pathogenic organism, a suitable environment,
and the right timing are present? - Answer Disease
If rodents are a problem during the winter, you should _______. - Answer Place a physical
barrier around the affected tree
A small, often microscopic, wormlike creature is called a(n) _______. - Answer Nematode
An important part of limb walking that helps maintain balance without putting excessive weight
on the tree is to _______. - Answer Keep your weight on the rope
Climbing spurs should be used only when working on trees _______. - Answer to be removed
where no electrical hazards exists
, A Prusik loop is used in climbing _______. - Answer to tie in for the secured footlock technique
When using a chain saw in a tree, a climber must _______. - Answer be secured with 2
separate lines such as a work-positioning lanyard and a climbing line, 2 climbing lines, or 2
lanyards
According to the ANSI Z133 safety standards, climbing lines must _________. - Answer have a
minimum tensile strength of at least 24.04 kN
The technique in which a climber ascends a tree by placing his or her feet high on the trunk and
thrusts the hips upward while pulling the slack out of the climbing line and advancing the
friction hitch is called _______ - Answer Body thrusting
Knots that tie two ropes together are known as_______. - Answer Bends
Which of the following statements about tree inspection and pre-climb inspection is true? -
Answer Before climbing a tree, the climber should check for hazards.
The recommended method for tying in is to pass the climbing line _______. - Answer Around a
leader and over a lateral
A technique in which a climber ties in on a second limb (or second tree) with the opposite end
of the climbing line or a second climbing line is called _______. - Answer Double crotching
If a pole pruner or a pole saw is used in a tree, _______. - Answer it should be hung in such a
way that the sharp edge is away from the worker and such that it cannot be accidentally
dislodged
When performing a pre-climb tree inspection, you should look for _________. - Answer
electrical conductors, stinging insects or other animal hazards, dead or broken limbs, decay,
cracks or other tree defects
If a victim appears to have a broken neck or spinal injury, and is breathing, what should you do?
- Answer Do not move the victim. make sure the victim is secure and his or her equipment is
secure, and wait for emergency help to arrive
A thin line with a throw weight/bag attached used to install a line in a tree is called a _______. -
Answer throwline
