C27 License Water Conservation and Drought-Tolerant Landscaping 2 — Questions and Answers
Question 1: Which irrigation method provides the greatest water conservation in a drought-tolerant landscape?
- Overhead spray sprinklers
- Drip irrigation (Correct answer)
- Flood irrigation
- Impact rotary heads
Correct answer: Drip irrigation
Drip irrigation delivers water directly to the root zone with minimal evaporation or runoff, making it the most water-efficient delivery method.
Question 2: What is the purpose of a rain sensor or weather-based controller in an irrigation system?
- To increase water pressure during dry periods
- To automatically shut off irrigation during or after rainfall (Correct answer)
- To detect underground pipe leaks
- To control fertilizer injection rates
Correct answer: To automatically shut off irrigation during or after rainfall
Rain sensors and weather-based controllers prevent irrigation from running during or after rainfall, reducing unnecessary water use.
Question 3: Which type of turf grass requires the least supplemental water in California landscapes?
- Kentucky Bluegrass
- St. Augustine grass
- Buffalo grass or Bermuda grass (Correct answer)
- Annual Ryegrass
Correct answer: Buffalo grass or Bermuda grass
Buffalo grass and Bermuda grass are warm-season grasses with deep root systems that require significantly less irrigation than cool-season varieties.
Question 4: What does 'water budget' mean in the context of California landscape water regulations?
- The contractor's estimated project cost
- The maximum annual water allowance for a landscape based on local ET data (Correct answer)
- The monthly cost of water for irrigation
- A financial reserve set aside for irrigation system repairs
Correct answer: The maximum annual water allowance for a landscape based on local ET data
A water budget is the Maximum Applied Water Allowance (MAWA) — the calculated annual water limit for a landscape based on local ET rates and total area.
Question 5: Which plants are most appropriate for drought-tolerant landscaping in California's climate?
- Tropical plants requiring frequent watering
- Native and Mediterranean-climate plants (Correct answer)
- Cool-season lawn grasses requiring daily irrigation
- Annuals requiring frequent replanting
Correct answer: Native and Mediterranean-climate plants
Native and Mediterranean-climate plants are adapted to California's dry summers and require minimal supplemental irrigation once established.
Question 6: What is the recommended soil amendment incorporation depth for turf removal and drought-tolerant replanting projects?
- 2 inches
- 4 inches
- 6 inches (Correct answer)
- 12 inches
Correct answer: 6 inches
For turf replacement projects, soil amendments should be incorporated to a depth of 6 inches to meaningfully improve water retention, drainage, and root penetration.
C27 License Water Conservation and Drought-Tolerant Landscaping 2
Which irrigation method provides the greatest water conservation in a drought-tolerant landscape?