Certified Arborist Test Tree Identification and Selection Questions and Answers — Questions and Answers
Question 1: A client wants to plant a large shade tree on the west side of their house to reduce summer cooling costs. The site is near the street and has overhead utility lines that are 25 feet high. Which of the following is the most appropriate tree selection?
- A small ornamental tree with a mature height of 20-25 feet. (Correct answer)
- A fast-growing deciduous tree like a silver maple (Acer saccharinum).
- A large deciduous tree like a red oak (Quercus rubra).
- A columnar evergreen tree like an arborvitae (Thuja occidentalis).
Correct answer: A small ornamental tree with a mature height of 20-25 feet.
The principle of "Right Tree, Right Place" dictates selecting a tree that will fit the available space at maturity without conflicting with infrastructure. Since the overhead utility lines are at 25 feet, choosing a small tree that matures at or below this height is essential to avoid future conflicts and the need for severe pruning. A large shade tree would grow into the lines, creating a hazard and maintenance issue. A columnar tree wouldn't provide the desired broad shade.
Question 2: When identifying a tree, an arborist notes that the leaves are attached to the twig in pairs, one directly across from the other at each node. What is this leaf arrangement called?
- Alternate
- Whorled
- Opposite (Correct answer)
- Pinnate
Correct answer: Opposite
Opposite leaf arrangement is characterized by two leaves growing directly across from each other at the same node on a twig. Alternate arrangement means one leaf per node, staggered along the twig. Whorled means three or more leaves per node. Pinnate refers to the arrangement of leaflets in a compound leaf, not the arrangement of leaves on a twig.
Question 3: A municipality is selecting trees for a new downtown streetscape. The planting sites are narrow pits surrounded by concrete, the soil is likely to be compacted and have a high pH, and the trees will be exposed to road salt in the winter. Which characteristic is MOST important for the selected tree species?
- Fast growth rate
- Showy spring flowers
- Broad, spreading canopy
- Tolerance to urban stress (Correct answer)
Correct answer: Tolerance to urban stress
Urban environments present significant challenges for trees, including compacted soil, limited root space, pollution, and de-icing salt exposure. Selecting species with a high tolerance for these specific urban stressors is the most critical factor for long-term survival and health. While other characteristics like form or flowers are desirable, they are secondary to the tree's ability to survive in the harsh conditions.
Question 4: Which of the following describes a tree with palmately compound leaves?
- A single leaf blade attached to the twig by a petiole.
- Leaflets are arranged along a central stalk, like a feather.
- Multiple leaflets arise from a single common point at the end of the petiole. (Correct answer)
- The leaf is divided into lobes, but the sinuses do not reach the midrib.
Correct answer: Multiple leaflets arise from a single common point at the end of the petiole.
In a palmately compound leaf, all the leaflets are attached at the same point at the tip of the petiole, resembling the fingers of a hand spreading from the palm. A simple leaf has a single blade. Pinnately compound leaves have leaflets arranged along a central axis (rachis). A lobed leaf is a type of simple leaf.
Question 5: A client in USDA Hardiness Zone 5b wants to plant a tree that is rated for Zone 7a. What is the most likely outcome if this tree is planted?
- The tree will grow faster than it would in Zone 7a.
- The tree is likely to suffer from winter injury or die. (Correct answer)
- The tree will be more resistant to local pests and diseases.
- The tree will require less water than a Zone 5b-rated tree.
Correct answer: The tree is likely to suffer from winter injury or die.
USDA Plant Hardiness Zones are based on the average annual minimum winter temperature. A tree rated for Zone 7a is adapted to a climate where the minimum temperatures are significantly warmer than in Zone 5b. Therefore, planting it in a colder zone makes it highly susceptible to damage or death from low winter temperatures it is not genetically equipped to handle.
Question 6: When evaluating a potential planting site, which factor is a key component of the "Right Tree, Right Place" principle?
- The current price of the tree at the nursery.
- The availability of seasonal discounts on fertilizer.
- The mature size of the tree and its proximity to infrastructure. (Correct answer)
- The popularity of the tree species on social media.
Correct answer: The mature size of the tree and its proximity to infrastructure.
The "Right Tree, Right Place" principle is a fundamental concept in arboriculture that emphasizes selecting a tree species whose mature characteristics (height, spread, root system) are compatible with the site's physical constraints. This includes considering space for both above-ground (canopy) and below-ground (roots) growth to avoid conflicts with buildings, utility lines, and pavement.
Certified Arborist Test Tree Identification and Selection Questions and Answers
A client wants to plant a large shade tree on the west side of their house to reduce summer cooling costs.
The site is near the street and has overhead utility lines that are 25 feet high.
Which of the following is the most appropriate tree selection?