CO Landscape Construction
Contractor Questions And Correct
Answers
(Verified Answers) Plus Rationale2026
Q&A| Instant Download Pdf
Which of the following is the primary purpose of a landscape plan?
A. Reduce water usage
B. Organize and guide construction and planting
C. Increase property taxes
D. Prevent erosion only
Rationale: A landscape plan provides a blueprint to organize construction,
planting, grading, and irrigation.
1. What is the ideal soil pH for most turfgrasses?
A. 4.5–5.5
B. 5.5–6.0
C. 6.0–7.0
D. 7.5–8.0
Rationale: Most turfgrasses thrive in slightly acidic to neutral soils,
typically 6.0–7.0.
2. Which of the following is a key factor when selecting plants for a
landscape project?
A. Popularity
B. Cost only
C. Climate, soil, and site conditions
D. Color alone
Rationale: Plant selection must consider environmental compatibility,
maintenance requirements, and site-specific conditions.
,3. What is the minimum slope recommended for proper drainage in
landscape grading?
A. 0.5%
B. 1%
C. 2%
D. 5%
Rationale: A slope of 2% (1/4 inch per foot) ensures adequate surface
drainage and prevents water pooling.
4. Which type of irrigation system is most water-efficient for trees and
shrubs?
A. Overhead sprinkler
B. Drip irrigation
C. Flood irrigation
D. Rotary sprinkler
Rationale: Drip irrigation delivers water directly to the root zone,
minimizing evaporation and runoff.
5. What is the purpose of a geotextile fabric in landscape construction?
A. Fertilize soil
B. Prevent plant growth
C. Separate soil layers and improve drainage
D. Hold mulch in place
Rationale: Geotextiles stabilize soil, prevent mixing of layers, and
enhance drainage.
6. When installing retaining walls, which factor is most critical to prevent
failure?
A. Color of stones
B. Proper drainage behind the wall
C. Wall height only
D. Plant selection
Rationale: Water pressure behind a retaining wall can cause
collapse; drainage systems prevent buildup.
7. Which type of mulch is best for moisture retention and weed
suppression?
A. Gravel
B. Sand
C. Organic mulch (e.g., wood chips, bark)
D. Concrete
, Rationale: Organic mulches help retain soil moisture, regulate
temperature, and suppress weeds.
8. When grading a landscape, what is the primary concern?
A. Ease of mowing
B. Proper drainage and erosion control
C. Plant aesthetics only
D. Cost reduction
Rationale: Correct grading ensures water flows away from structures
and prevents soil erosion.
9. Which of the following is an advantage of using native plants?
A. Require more water
B. Require heavy fertilization
C. Attract pests
D. Adapted to local climate and soil
Rationale: Native plants are more resilient, require less maintenance,
and support local wildlife.
10. Which type of tree root system is more effective at preventing
soil erosion?
A. Taproot only
B. Fibrous root system
C. Shallow roots
D. None of the above
Rationale: Fibrous roots spread widely and hold soil effectively,
reducing erosion risks.
11. What is the recommended spacing for most shrubs in a formal
hedge?
A. 6 inches
B. 12 inches
C. 24–36 inches
D. 48 inches
Rationale: Proper spacing allows mature growth without
overcrowding while maintaining visual appeal.
12. Which factor affects the lifespan of landscape hardscapes?
A. Plant type
B. Material quality and installation methods
C. Mulch color
D. Irrigation frequency
Contractor Questions And Correct
Answers
(Verified Answers) Plus Rationale2026
Q&A| Instant Download Pdf
Which of the following is the primary purpose of a landscape plan?
A. Reduce water usage
B. Organize and guide construction and planting
C. Increase property taxes
D. Prevent erosion only
Rationale: A landscape plan provides a blueprint to organize construction,
planting, grading, and irrigation.
1. What is the ideal soil pH for most turfgrasses?
A. 4.5–5.5
B. 5.5–6.0
C. 6.0–7.0
D. 7.5–8.0
Rationale: Most turfgrasses thrive in slightly acidic to neutral soils,
typically 6.0–7.0.
2. Which of the following is a key factor when selecting plants for a
landscape project?
A. Popularity
B. Cost only
C. Climate, soil, and site conditions
D. Color alone
Rationale: Plant selection must consider environmental compatibility,
maintenance requirements, and site-specific conditions.
,3. What is the minimum slope recommended for proper drainage in
landscape grading?
A. 0.5%
B. 1%
C. 2%
D. 5%
Rationale: A slope of 2% (1/4 inch per foot) ensures adequate surface
drainage and prevents water pooling.
4. Which type of irrigation system is most water-efficient for trees and
shrubs?
A. Overhead sprinkler
B. Drip irrigation
C. Flood irrigation
D. Rotary sprinkler
Rationale: Drip irrigation delivers water directly to the root zone,
minimizing evaporation and runoff.
5. What is the purpose of a geotextile fabric in landscape construction?
A. Fertilize soil
B. Prevent plant growth
C. Separate soil layers and improve drainage
D. Hold mulch in place
Rationale: Geotextiles stabilize soil, prevent mixing of layers, and
enhance drainage.
6. When installing retaining walls, which factor is most critical to prevent
failure?
A. Color of stones
B. Proper drainage behind the wall
C. Wall height only
D. Plant selection
Rationale: Water pressure behind a retaining wall can cause
collapse; drainage systems prevent buildup.
7. Which type of mulch is best for moisture retention and weed
suppression?
A. Gravel
B. Sand
C. Organic mulch (e.g., wood chips, bark)
D. Concrete
, Rationale: Organic mulches help retain soil moisture, regulate
temperature, and suppress weeds.
8. When grading a landscape, what is the primary concern?
A. Ease of mowing
B. Proper drainage and erosion control
C. Plant aesthetics only
D. Cost reduction
Rationale: Correct grading ensures water flows away from structures
and prevents soil erosion.
9. Which of the following is an advantage of using native plants?
A. Require more water
B. Require heavy fertilization
C. Attract pests
D. Adapted to local climate and soil
Rationale: Native plants are more resilient, require less maintenance,
and support local wildlife.
10. Which type of tree root system is more effective at preventing
soil erosion?
A. Taproot only
B. Fibrous root system
C. Shallow roots
D. None of the above
Rationale: Fibrous roots spread widely and hold soil effectively,
reducing erosion risks.
11. What is the recommended spacing for most shrubs in a formal
hedge?
A. 6 inches
B. 12 inches
C. 24–36 inches
D. 48 inches
Rationale: Proper spacing allows mature growth without
overcrowding while maintaining visual appeal.
12. Which factor affects the lifespan of landscape hardscapes?
A. Plant type
B. Material quality and installation methods
C. Mulch color
D. Irrigation frequency
