ISA CERTIFIED ARBORIST EXAM
WITH QUESTIONS AND 100%
CORRECT ANSWERS A+ GRADED
LATEST VERSION 2026
ISA Certified Arborist Exam - answer-Exam Coverage
The exam coverage includes the fundamental knowledge and professional practices
required for the International Society of Arboriculture Certified Arborist Exam. It focuses
on tree biology, identification and selection, soil management, water management, tree
nutrition, pruning techniques, and diagnosis and treatment of tree diseases and pests.
The exam also assesses understanding of tree risk assessment, safe work practices,
planting and establishment, urban forestry principles, and proper tree care practices to
promote tree health and safety in residential, commercial, and municipal environments
7-Strand, Common Grade Cable - answer-Steel-cable construction in which seven
strands are twisted together in a spiral pattern. Used to add supplemental structural
support to trees.
12-Strand Rope - answer-For arborist ropes, a braided rope consisting of 12 strands.
Most are coreless.
What are the two types of 12 strand ropes? - answer-Tight braid and loose braid.
3-Strand Rope - answer-Rope construction in which three strands are twisted together
in a spiral pattern.
Tight Braid - answer-It is not easily spliceable, used for climbing and rigging lines.
Loose Braid - answer-Easily spliceable braid, commonly used for slings.
,16-Strand Rope - answer-For arborist ropes, a braided rope that has a 16-strand, load-
bearing cover and a filler core that is not significant in load carrying.
24-Strand Rope - answer-For arborist ropes, a braided rope that has a 24-strand cover
and is available in double braid or kernmantle construction.
Abiotic Disorder - answer-Plant malady caused by nonliving, environmental, or man-
made agents.
Abscission Zone - answer-Area at the base of the petiole where cellular breakdown
leads to leaf and fruit drop.
Absorbing Roots - answer-Fine, fibrous roots that take up water and minerals. Most are
within the top 12 inches of soil.
Access Line - answer-1) Second climbing line hung in a tree in case it is needed to reach
a victim in an emergency. 2) Climbing line installed in a tree to gain access to, but not
use to work in, the tree.
Access Route - answer-Defined entrance and exit route for a property during
construction, tree work, or landscape operations.
Acclimation - answer-Physiological adaption process of plants and other living
organisms to a climate or environment different from their native environment or where
originally grown.
Actinomycetes - answer-Group of soil bacteria resembling fungi. Actinomycetes play a
role in the decomposition of organic matter and the release of mineral elements.
Action Threshold - answer-Pest population or plant damage level that requires action to
prevent irreversible or unacceptable physiological and/or aesthetic harm.
,Acute - answer-Disorder or disease that occurs suddenly or over a short period of time.
Contrast with chronic.
Adaptability - answer-Genetic ability of plants and other living organisms to adjust or
acclimate to different environments.
Adventitious Bud - answer-Bud arising from a place other than a leaf axil or shoot tip,
usually as a result of hormonal triggers.
Aerial Rescue - answer-Method of bringing an injured worker down from a tree or aerial
lift device.
Aerial Roots - answer-Aboveground roots. Usually adventitious in nature and sometimes
having unique adaptive functions.
Aerobic - answer-With oxygen. Process that occurs in the presence of oxygen.
Aggregate - answer-1) Close cluster or mix of small particles of soil and/or organic
matter of varying sizes that are bonded together; sand, gravel, or small rocks in soil;
and/or sand, gravel, or small rocks used under paved surfaces.
Aggregate - answer-Clusters of flowers or fruits that appear as a single unit.
Aggregate - answer-Individual tree crowns that form a canopy.
Air Excavation Device, Air Excavator - answer-Device that directs a jet of highly
compressed air to excavate soil.
When is an air excavation device used? - answer-Used within the root zone of trees to
avoid or minimize damage to the roots, or near underground structures such as pipes
and wires to avoid or minimize damage to them.
, Air Terminal - answer-Uppermost point of a tree lighting protection system.
Aircraft Cable - answer-Steel wire rope of various constructions designated by the
number of strands in the rope and the number of wires in each strand.
Allelochemical - answer-Substance produced naturally by plants as part of a defense
against pests and other plants. May affect the growth and development of other plants.
Allelopathy - answer-Chemical effect or inhibition of growth or development of plants
that is induced by allelochemicals.
Alternate - answer-Pertaining to bud or leaf arrangement, one leaf or bud at each node,
situated at alternating positions along the stem. In this arrangement, the leaves are not
directly across from each other.
Amon-eye Nut - answer-Specialized nut used in cabling trees that has a large eye for
attaching a cable to a threaded rod.
Anaerobic - answer-Without oxygen. Process that occurs in the absence of oxygen.
Anchor Hardware - answer-Hardware to which the cable termination is affixed in a
cabling or guying installation.
Angiosperm - answer-Plant with seeds borne in an ovary. Consists of two large groups:
monocotyledons (grasses, palms, and related plants) and dicotyledons (most woody
trees, shrubs, herbaceous plants, and related plants).
Anion - answer-Ion that carries a negative charge. Contrast with cation.
WITH QUESTIONS AND 100%
CORRECT ANSWERS A+ GRADED
LATEST VERSION 2026
ISA Certified Arborist Exam - answer-Exam Coverage
The exam coverage includes the fundamental knowledge and professional practices
required for the International Society of Arboriculture Certified Arborist Exam. It focuses
on tree biology, identification and selection, soil management, water management, tree
nutrition, pruning techniques, and diagnosis and treatment of tree diseases and pests.
The exam also assesses understanding of tree risk assessment, safe work practices,
planting and establishment, urban forestry principles, and proper tree care practices to
promote tree health and safety in residential, commercial, and municipal environments
7-Strand, Common Grade Cable - answer-Steel-cable construction in which seven
strands are twisted together in a spiral pattern. Used to add supplemental structural
support to trees.
12-Strand Rope - answer-For arborist ropes, a braided rope consisting of 12 strands.
Most are coreless.
What are the two types of 12 strand ropes? - answer-Tight braid and loose braid.
3-Strand Rope - answer-Rope construction in which three strands are twisted together
in a spiral pattern.
Tight Braid - answer-It is not easily spliceable, used for climbing and rigging lines.
Loose Braid - answer-Easily spliceable braid, commonly used for slings.
,16-Strand Rope - answer-For arborist ropes, a braided rope that has a 16-strand, load-
bearing cover and a filler core that is not significant in load carrying.
24-Strand Rope - answer-For arborist ropes, a braided rope that has a 24-strand cover
and is available in double braid or kernmantle construction.
Abiotic Disorder - answer-Plant malady caused by nonliving, environmental, or man-
made agents.
Abscission Zone - answer-Area at the base of the petiole where cellular breakdown
leads to leaf and fruit drop.
Absorbing Roots - answer-Fine, fibrous roots that take up water and minerals. Most are
within the top 12 inches of soil.
Access Line - answer-1) Second climbing line hung in a tree in case it is needed to reach
a victim in an emergency. 2) Climbing line installed in a tree to gain access to, but not
use to work in, the tree.
Access Route - answer-Defined entrance and exit route for a property during
construction, tree work, or landscape operations.
Acclimation - answer-Physiological adaption process of plants and other living
organisms to a climate or environment different from their native environment or where
originally grown.
Actinomycetes - answer-Group of soil bacteria resembling fungi. Actinomycetes play a
role in the decomposition of organic matter and the release of mineral elements.
Action Threshold - answer-Pest population or plant damage level that requires action to
prevent irreversible or unacceptable physiological and/or aesthetic harm.
,Acute - answer-Disorder or disease that occurs suddenly or over a short period of time.
Contrast with chronic.
Adaptability - answer-Genetic ability of plants and other living organisms to adjust or
acclimate to different environments.
Adventitious Bud - answer-Bud arising from a place other than a leaf axil or shoot tip,
usually as a result of hormonal triggers.
Aerial Rescue - answer-Method of bringing an injured worker down from a tree or aerial
lift device.
Aerial Roots - answer-Aboveground roots. Usually adventitious in nature and sometimes
having unique adaptive functions.
Aerobic - answer-With oxygen. Process that occurs in the presence of oxygen.
Aggregate - answer-1) Close cluster or mix of small particles of soil and/or organic
matter of varying sizes that are bonded together; sand, gravel, or small rocks in soil;
and/or sand, gravel, or small rocks used under paved surfaces.
Aggregate - answer-Clusters of flowers or fruits that appear as a single unit.
Aggregate - answer-Individual tree crowns that form a canopy.
Air Excavation Device, Air Excavator - answer-Device that directs a jet of highly
compressed air to excavate soil.
When is an air excavation device used? - answer-Used within the root zone of trees to
avoid or minimize damage to the roots, or near underground structures such as pipes
and wires to avoid or minimize damage to them.
, Air Terminal - answer-Uppermost point of a tree lighting protection system.
Aircraft Cable - answer-Steel wire rope of various constructions designated by the
number of strands in the rope and the number of wires in each strand.
Allelochemical - answer-Substance produced naturally by plants as part of a defense
against pests and other plants. May affect the growth and development of other plants.
Allelopathy - answer-Chemical effect or inhibition of growth or development of plants
that is induced by allelochemicals.
Alternate - answer-Pertaining to bud or leaf arrangement, one leaf or bud at each node,
situated at alternating positions along the stem. In this arrangement, the leaves are not
directly across from each other.
Amon-eye Nut - answer-Specialized nut used in cabling trees that has a large eye for
attaching a cable to a threaded rod.
Anaerobic - answer-Without oxygen. Process that occurs in the absence of oxygen.
Anchor Hardware - answer-Hardware to which the cable termination is affixed in a
cabling or guying installation.
Angiosperm - answer-Plant with seeds borne in an ovary. Consists of two large groups:
monocotyledons (grasses, palms, and related plants) and dicotyledons (most woody
trees, shrubs, herbaceous plants, and related plants).
Anion - answer-Ion that carries a negative charge. Contrast with cation.
