ISA Tree Selection and Planting 1 — Questions and Answers
Question 1: Which principle best describes selecting a tree species whose mature size, form, and cultural needs match the available space and site conditions?
- Integrated pest management
- Right tree, right place (Correct answer)
- Succession planting
- Canopy layering
Correct answer: Right tree, right place
The 'right tree, right place' principle ensures long-term tree health by matching species requirements to existing site conditions and spatial constraints.
Question 2: When evaluating an urban planting site, which soil characteristic is most critical to assess first?
- Soil color and texture
- Soil drainage (Correct answer)
- Soil nitrogen content
- Percentage of organic matter
Correct answer: Soil drainage
Poor drainage leads to anaerobic conditions that suffocate roots and is one of the leading causes of tree decline, making it the most critical factor to assess.
Question 3: What does a USDA Plant Hardiness Zone designation primarily indicate for tree selection?
- Maximum height a tree will reach in that region
- Minimum average annual temperature a plant can survive (Correct answer)
- The tree's tolerance to drought and heat stress
- Pest and disease pressure in a geographic area
Correct answer: Minimum average annual temperature a plant can survive
USDA Hardiness Zones are based on average minimum winter temperatures, indicating whether a plant can survive winter cold in a given location.
Question 4: Which tree growth form is MOST appropriate for planting in corridors beneath overhead utility lines?
- Excurrent (strong central leader)
- Decurrent (spreading crown)
- Columnar or fastigiate (Correct answer)
- Weeping or pendulous
Correct answer: Columnar or fastigiate
Columnar or fastigiate trees have a narrow, upright growth habit that minimizes horizontal spread and conflict with overhead utilities.
Question 5: When selecting trees for a site with chronically compacted soils, which characteristic is MOST desirable?
- Rapid juvenile growth rate
- Tolerance of reduced oxygen in the root zone (Correct answer)
- High supplemental irrigation requirements
- Very shallow rooting habit
Correct answer: Tolerance of reduced oxygen in the root zone
Compacted soils have reduced pore space and lower oxygen levels; selecting species tolerant of low oxygen ensures better establishment and long-term survival.
Question 6: A tree being considered for a parking lot island should be evaluated primarily for tolerance of:
- Moderate shade and cool temperatures
- Heat, drought, and reflected radiation from pavement (Correct answer)
- High soil moisture and humidity
- Competition from turfgrass
Correct answer: Heat, drought, and reflected radiation from pavement
Parking lot environments create extreme heat, drought, and radiant heat stress from surrounding pavement, requiring species with high tolerance for these stressors.
Question 7: Which factor is MOST important when determining the appropriate canopy spread of a tree selected for a residential planting?
- Aesthetic preference of the homeowner
- Proximity to overhead utilities, structures, and property lines at maturity (Correct answer)
- Availability of the species at local nurseries
- The current size of the nursery stock
Correct answer: Proximity to overhead utilities, structures, and property lines at maturity
The tree's canopy spread at full maturity must be evaluated in relation to overhead utilities, buildings, and property lines to prevent future conflicts.
ISA Tree Selection and Planting 1
Which principle best describes selecting a tree species whose mature size, form, and cultural needs match the available space and site conditions?