CFA Best Practices for Application 3 — Questions and Answers
Question 1: What is the purpose of a split application approach when fertilizing turf?
- To apply different fertilizer products at the same time
- To divide the annual nutrient dose into multiple smaller applications (Correct answer)
- To split the lawn into zones and apply separately
- To alternate between liquid and granular products each season
Correct answer: To divide the annual nutrient dose into multiple smaller applications
Split applications divide the total annual fertilizer dose into multiple smaller doses throughout the season, improving nutrient uptake and reducing leaching risk.
Question 2: An applicator notices excessive fertilizer has been accidentally applied to one area. What is the correct immediate action?
- Apply lime to neutralize the excess fertilizer
- Water the area thoroughly to dilute and move nutrients into the soil (Correct answer)
- Remove the top layer of soil from the affected area
- Apply a herbicide to prevent weed growth from the excess nutrients
Correct answer: Water the area thoroughly to dilute and move nutrients into the soil
Thorough irrigation immediately after an over-application helps dilute soluble nutrients and move them into the root zone, reducing the risk of fertilizer burn and runoff.
Question 3: Which of the following is a key reason to avoid fertilizing during drought stress?
- Fertilizer increases water demand and worsens drought stress (Correct answer)
- Dry conditions cause fertilizer to convert into toxic compounds
- Grass is dormant and cannot be damaged during drought
- Fertilizer evaporates before it can reach the root zone
Correct answer: Fertilizer increases water demand and worsens drought stress
Fertilizing during drought increases plant nutrient demand and water uptake requirements at a time when water is scarce, worsening drought stress and potentially causing fertilizer burn.
Question 4: When is the best time to apply a pre-emergent weed preventer combined with fertilizer (weed-and-feed)?
- Immediately after mowing when grass is stressed
- Just before weed seeds germinate in early spring or fall (Correct answer)
- In midsummer when weeds are actively growing
- After heavy rain when soil is saturated
Correct answer: Just before weed seeds germinate in early spring or fall
Weed-and-feed products with pre-emergent herbicides must be applied just before target weed seeds germinate to create an effective chemical barrier in the soil.
Question 5: What does a 'blackout period' for fertilization typically refer to in coastal states?
- A period when fertilizer must be applied only at night to avoid heat
- A seasonal prohibition on fertilizer use to protect water quality (Correct answer)
- A mandatory rest period for application equipment
- A time when fertilizer prices are restricted by law
Correct answer: A seasonal prohibition on fertilizer use to protect water quality
Many coastal states impose seasonal fertilizer blackout periods, typically during the rainy season, to prevent nutrient runoff from entering sensitive water bodies.
Question 6: Why should phosphorus fertilizers be used sparingly or avoided on established lawns in many states?
- Phosphorus causes grass blades to turn yellow
- Established turf soils often already have sufficient phosphorus levels (Correct answer)
- Phosphorus fertilizers are too acidic for most grasses
- Phosphorus prevents the uptake of nitrogen and potassium
Correct answer: Established turf soils often already have sufficient phosphorus levels
Established lawns typically accumulate sufficient phosphorus over time, and adding more increases the risk of phosphorus runoff into waterways, causing algae blooms.
Question 7: Which practice best reduces the risk of fertilizer leaching below the root zone?
- Using high application rates to saturate the root zone
- Applying slow-release formulations and avoiding over-irrigation (Correct answer)
- Incorporating fertilizer deeply into the soil before planting
- Applying all annual fertilizer in a single large dose
Correct answer: Applying slow-release formulations and avoiding over-irrigation
Slow-release fertilizers and controlled irrigation keep nutrients within the root zone longer, reducing the risk of leaching into groundwater.
CFA Best Practices for Application 3
What is the purpose of a split application approach when fertilizing turf?