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ISA ARBORIST STUDY GUIDE
QUESTIONS AND ANSWERS 2025
Bark, phloem, cambium, xylem - correct answer- When cutting
through a tree with a chain saw or drilling into a tree, you would
pass through (in order)
Growth may be stimulated in lateral buds - correct answer- If
the terminal bud is removed in pruning:
The growth rings of a tree: - correct answer- Visible because of
the rapid growth rate of earlywood relative to latewood, can be
counted on to approximate trees age, can give information
about growth conditions in previous years.
Cambium - correct answer- layer of cells is responsible for
outward growth and increased girth of tree.
Mycorrhizae are: - correct answer- A symbiotic relationship
between fungi and roots.
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Douglas-fir (Pseudotsuga menziesii) differs from balsam fir
(Abies balsamea) in that: - correct answer- They are not in the
same genus.
Opposite leaf arrangement is: - correct answer- When two
leaves and/or buds are located at the same node on a twig.
Quercus rubra - correct answer- Scientific name of Red Oak.
Quercus (Oak) - correct answer- This genus of tree usually
does not have an opposite leaf arrangement.
Pines - correct answer- These conifers have needles in
bundles.
Available oxygen and water - correct answer- The primary
factor in controlling the depth, spread, and distribution of tree
roots in the soil is/are:
The most fibrous and absorptive portion of a tree's root system
is found in? - correct answer- Are in the upper 6 inches of soil.
ISA ARBORIST STUDY GUIDE
QUESTIONS AND ANSWERS 2025
Bark, phloem, cambium, xylem - correct answer- When cutting
through a tree with a chain saw or drilling into a tree, you would
pass through (in order)
Growth may be stimulated in lateral buds - correct answer- If
the terminal bud is removed in pruning:
The growth rings of a tree: - correct answer- Visible because of
the rapid growth rate of earlywood relative to latewood, can be
counted on to approximate trees age, can give information
about growth conditions in previous years.
Cambium - correct answer- layer of cells is responsible for
outward growth and increased girth of tree.
Mycorrhizae are: - correct answer- A symbiotic relationship
between fungi and roots.
, 2 | Page
Douglas-fir (Pseudotsuga menziesii) differs from balsam fir
(Abies balsamea) in that: - correct answer- They are not in the
same genus.
Opposite leaf arrangement is: - correct answer- When two
leaves and/or buds are located at the same node on a twig.
Quercus rubra - correct answer- Scientific name of Red Oak.
Quercus (Oak) - correct answer- This genus of tree usually
does not have an opposite leaf arrangement.
Pines - correct answer- These conifers have needles in
bundles.
Available oxygen and water - correct answer- The primary
factor in controlling the depth, spread, and distribution of tree
roots in the soil is/are:
The most fibrous and absorptive portion of a tree's root system
is found in? - correct answer- Are in the upper 6 inches of soil.
