CH Turfgrass Management 1 — Questions and Answers
Question 1: Which of the following is classified as a cool-season turfgrass?
- Bermudagrass
- Kentucky bluegrass (Correct answer)
- Zoysiagrass
- St. Augustinegrass
Correct answer: Kentucky bluegrass
Kentucky bluegrass is a cool-season grass that grows best at 60–75°F, unlike the warm-season grasses listed.
Question 2: What is the primary purpose of core aeration in turfgrass management?
- To increase soil pH
- To reduce thatch accumulation
- To relieve soil compaction and improve air, water, and nutrient movement (Correct answer)
- To introduce new grass seed
Correct answer: To relieve soil compaction and improve air, water, and nutrient movement
Core aeration removes plugs of soil to relieve compaction and improve the movement of air, water, and nutrients to the root zone.
Question 3: Thatch in a turfgrass stand is best described as:
- Dead grass clippings left on the lawn surface
- A layer of living and dead organic matter between the soil surface and green grass (Correct answer)
- A fungal disease affecting turfgrass crowns
- A type of soil amendment used during turf renovation
Correct answer: A layer of living and dead organic matter between the soil surface and green grass
Thatch is the layer of accumulated living and dead organic matter (stems, roots, rhizomes) situated between the soil surface and the actively growing green grass.
Question 4: What mowing height is generally recommended for Kentucky bluegrass during summer stress periods?
- 0.5–1 inch
- 1–1.5 inches
- 2.5–3.5 inches (Correct answer)
- 4–5 inches
Correct answer: 2.5–3.5 inches
Kentucky bluegrass is typically maintained at 2.5–3.5 inches in summer to promote deeper roots and improve heat and drought stress tolerance.
Question 5: Which warm-season turfgrass has the highest shade tolerance?
- Bermudagrass
- Zoysiagrass
- Centipedegrass
- St. Augustinegrass (Correct answer)
Correct answer: St. Augustinegrass
St. Augustinegrass has the best shade tolerance among commonly used warm-season grasses, making it suitable for partially shaded lawns in the South.
Question 6: The 'one-third rule' in turfgrass mowing states that you should never remove more than one-third of the:
- Total root mass in a single season
- Leaf blade height in a single mowing (Correct answer)
- Lawn area in one mowing session
- Annual fertilizer budget at once
Correct answer: Leaf blade height in a single mowing
The one-third rule states that no more than one-third of the leaf blade should be removed in a single mowing to minimize plant stress and protect photosynthetic capacity.
Question 7: Overseeding dormant warm-season turf with annual or perennial ryegrass in the fall is primarily done to:
- Permanently replace the warm-season grass with a cool-season species
- Maintain green color during the winter dormancy period (Correct answer)
- Prevent summer annual weed germination the following spring
- Reduce irrigation requirements during winter months
Correct answer: Maintain green color during the winter dormancy period
Overseeding dormant warm-season turf with ryegrass provides green winter color while the base warm-season grass is dormant.
CH Turfgrass Management 1
Which of the following is classified as a cool-season turfgrass?