ISA ARBORIST FINAL PAPER 191 2026 FULL
QUESTIONS AND CORRECT ANSWERS
GRADED A+
◉ 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.
◉ ANSI A300. Answer: In the United States, industry developed,
national consensus standards of practice for tree care.
,◉ ANSI Z133.1. Answer: In the United States, industry developed,
national consensus safety standards of practice for tree care.
◉ Anthocyanin. Answer: Red or purple pigment responsible for
those colors in some parts of trees and other plants.
◉ Antigibberellin. Answer: Plant growth regulator that inhibits the
action of the plant hormone gibberellin, which, among other things,
regulates cell elongation.
◉ Antitranspirant. Answer: Substance applied to the foliage of
plants to reduce water loss (transpiration).
◉ Apical Bud. Answer: Bud at the tip of twig or shoot.
◉ Apical Control. Answer: Inhibition of lateral buds, decreasing from
the top down, by apical buds over many seasons, resulting in trees
with an excurrent growth form.
◉ Apical Dominance. Answer: Condition in which the terminal bud
inhibits the growth and development of lateral buds on the same
stem formed during the same season.
,◉ Apical Meristem. Answer: Growing point at the tips of shoots and
roots.
◉ Apoplasm. Answer: Free spaces in pant tissue. Includes cell walls
and intercellular spaces. Contrast with symplasm.
◉ Appropriate Response Process. Answer: Method of systematically
assessing plant health and client needs to determine which course of
action, if any, is recommended.
◉ Approved. Answer: in the context of guidelines, standards, and
specifications, that which is acceptable to federal, state, provincial,
or local enforcement authorities or is an accepted industry practice.
◉ Arboriculture. Answer: Practice and study of the care of trees and
other woody plants in landscape.
◉ Arborist Block. Answer: Heavy-duty pulley with an integrated
connection point (bushing for attaching a rope sling), a rotating
sheave for the rope, and extended cheek plates. Used in tree rigging.
◉ Ascender. Answer: Piece of gear that enables a climber to ascend a
rope. Attached to the rope, it will grip in one direction (down) and
slide in the other (up).
, ◉ Augmentation. Answer: In Plant Health Care, the release of
beneficial organisms to suppress pest insect or mite populations.
◉ Auxin. Answer: Plant hormone or substance that promotes or
regulates the growth and development of plants. Produced at sites
where cells are dividing, primarily in the shoot tips. Auxin-like
compounds may be synthetically produced.
◉ Available Water. Answer: Water remaining in the soil after
gravitational water has drained and before the permanent wilting
point has been reached.
◉ Axial Transport. Answer: Movement of water, minerals, or
photosynthates longitudinally within a tree.
◉ Axillary Bud. Answer: Bud in the axil of a leaf. Lateral bud.
◉ Back Cut. Answer: Cut made on a tree trunk or branch, opposite
from and toward the notch, face cut, or undercut, to complete felling
or branch removal.
◉ Bactericide. Answer: Pesticide that is used to kill or inhibit
bacteria in plants or soil.
QUESTIONS AND CORRECT ANSWERS
GRADED A+
◉ 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.
◉ ANSI A300. Answer: In the United States, industry developed,
national consensus standards of practice for tree care.
,◉ ANSI Z133.1. Answer: In the United States, industry developed,
national consensus safety standards of practice for tree care.
◉ Anthocyanin. Answer: Red or purple pigment responsible for
those colors in some parts of trees and other plants.
◉ Antigibberellin. Answer: Plant growth regulator that inhibits the
action of the plant hormone gibberellin, which, among other things,
regulates cell elongation.
◉ Antitranspirant. Answer: Substance applied to the foliage of
plants to reduce water loss (transpiration).
◉ Apical Bud. Answer: Bud at the tip of twig or shoot.
◉ Apical Control. Answer: Inhibition of lateral buds, decreasing from
the top down, by apical buds over many seasons, resulting in trees
with an excurrent growth form.
◉ Apical Dominance. Answer: Condition in which the terminal bud
inhibits the growth and development of lateral buds on the same
stem formed during the same season.
,◉ Apical Meristem. Answer: Growing point at the tips of shoots and
roots.
◉ Apoplasm. Answer: Free spaces in pant tissue. Includes cell walls
and intercellular spaces. Contrast with symplasm.
◉ Appropriate Response Process. Answer: Method of systematically
assessing plant health and client needs to determine which course of
action, if any, is recommended.
◉ Approved. Answer: in the context of guidelines, standards, and
specifications, that which is acceptable to federal, state, provincial,
or local enforcement authorities or is an accepted industry practice.
◉ Arboriculture. Answer: Practice and study of the care of trees and
other woody plants in landscape.
◉ Arborist Block. Answer: Heavy-duty pulley with an integrated
connection point (bushing for attaching a rope sling), a rotating
sheave for the rope, and extended cheek plates. Used in tree rigging.
◉ Ascender. Answer: Piece of gear that enables a climber to ascend a
rope. Attached to the rope, it will grip in one direction (down) and
slide in the other (up).
, ◉ Augmentation. Answer: In Plant Health Care, the release of
beneficial organisms to suppress pest insect or mite populations.
◉ Auxin. Answer: Plant hormone or substance that promotes or
regulates the growth and development of plants. Produced at sites
where cells are dividing, primarily in the shoot tips. Auxin-like
compounds may be synthetically produced.
◉ Available Water. Answer: Water remaining in the soil after
gravitational water has drained and before the permanent wilting
point has been reached.
◉ Axial Transport. Answer: Movement of water, minerals, or
photosynthates longitudinally within a tree.
◉ Axillary Bud. Answer: Bud in the axil of a leaf. Lateral bud.
◉ Back Cut. Answer: Cut made on a tree trunk or branch, opposite
from and toward the notch, face cut, or undercut, to complete felling
or branch removal.
◉ Bactericide. Answer: Pesticide that is used to kill or inhibit
bacteria in plants or soil.
