CFA Fertilizer Application Equipment 3 — Questions and Answers
Question 1: A subsurface band applicator places fertilizer in the soil primarily to:
- Reduce equipment purchase costs
- Minimize fertilizer contact with seeds and improve nutrient placement (Correct answer)
- Speed up application compared to broadcast spreading
- Avoid the need for soil testing
Correct answer: Minimize fertilizer contact with seeds and improve nutrient placement
Subsurface banding minimizes seed-fertilizer contact that can cause salt injury and places nutrients closer to root zones for more efficient uptake.
Question 2: What is the function of a jet agitator in a liquid fertilizer nurse tank?
- To pump fertilizer from tank to boom
- To keep liquid fertilizer uniformly mixed using recirculating liquid jets (Correct answer)
- To measure tank volume remaining
- To filter large particles before pumping
Correct answer: To keep liquid fertilizer uniformly mixed using recirculating liquid jets
Jet agitators recirculate liquid through nozzles submerged in the tank, keeping mixed fertilizers and suspension products uniformly blended.
Question 3: Which factor most significantly affects the spread width of a rotary spinner spreader?
- Ambient temperature
- Spinner disc rotation speed and granule size/density (Correct answer)
- Color of the fertilizer product
- Soil moisture content
Correct answer: Spinner disc rotation speed and granule size/density
Spinner disc RPM combined with fertilizer granule size and density determines how far and wide granules are thrown from the spreader.
Question 4: What is 'streaking' in the context of liquid boom fertilizer application?
- Applying fertilizer at night
- Visible lines of over- or under-application caused by nozzle problems (Correct answer)
- Moving the sprayer too quickly across the field
- Mixing incompatible fertilizer products
Correct answer: Visible lines of over- or under-application caused by nozzle problems
Streaking refers to visible bands of uneven application, typically caused by clogged, worn, or mismatched nozzles on the boom.
Question 5: An anhydrous ammonia applicator must use which type of specialized hose for transferring the product?
- Standard garden hose rated for water
- High-pressure hose rated for anhydrous ammonia service (Correct answer)
- PVC tubing with standard fittings
- Flexible rubber hose used for diesel fuel
Correct answer: High-pressure hose rated for anhydrous ammonia service
Anhydrous ammonia requires specially rated hoses and fittings that resist its corrosive and pressure properties to prevent leaks and failures.
Question 6: What does a GPS variable rate application (VRA) controller allow an applicator to do?
- Drive the tractor automatically without an operator
- Automatically adjust fertilizer application rates based on field prescription maps (Correct answer)
- Eliminate the need for soil sampling
- Apply fertilizer without a boom or spreader
Correct answer: Automatically adjust fertilizer application rates based on field prescription maps
VRA controllers receive GPS position data and adjust application rates in real time to match prescription maps based on soil variability.
Question 7: Why should liquid fertilizer booms be flushed with clean water before storing equipment for extended periods?
- To improve fertilizer solubility for the next use
- To prevent nozzle and line corrosion from residual fertilizer salts (Correct answer)
- To increase pump pressure for next application
- To cool down the pump after operation
Correct answer: To prevent nozzle and line corrosion from residual fertilizer salts
Residual fertilizer salts in lines and nozzles can crystallize and corrode metal parts or clog nozzles during storage.
CFA Fertilizer Application Equipment 3
A subsurface band applicator places fertilizer in the soil primarily to: