Examination with Practice Questions And
Correct Answers (
1. A restricted-use pesticide label states: 'Do not apply within 100 feet of any well,
sinkhole, or surface water.' A grower wants to apply the product to a field where a dry
ditch connects to a creek 300 feet away. Under California regulation, which statement
best describes the legal application?
A. Application is allowed because the ditch is dry and the creek is beyond the 100-foot
buffer.
B. Application is prohibited within 100 feet of the ditch because it is a conduit to surface
water.
C. Application is allowed if the applicator uses a hooded sprayer to reduce drift.
D. Application is prohibited only if the ditch contains standing water at the time of
application.
Answer: B. Application is prohibited within 100 feet of the ditch because it is a conduit
to surface water.
Rationale: California regulations define 'surface water' to include dry ditches that may
carry water to a creek, so the 100-foot buffer applies. Options A, C, and D incorrectly
assume the ditch is exempt or that equipment modifications override the buffer
requirement.
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,2. A pesticide applicator is mixing a concentrated organophosphate in a closed system.
Which of the following is the most critical factor in selecting chemical-resistant gloves
according to the EPA's PPE guidelines?
A. The glove material's breakthrough time for the specific pesticide formulation.
B. The glove thickness measured in mils, with thicker always being better.
C. The color of the glove to indicate chemical resistance category.
D. The length of the glove extending past the wrist.
Answer: A. The glove material's breakthrough time for the specific pesticide
formulation.
Rationale: EPA's PPE guidance emphasizes breakthrough time and permeation rate for the
specific chemical; thickness alone (B) is not a reliable indicator, color (C) is not
standardized, and length (D) is secondary to material performance.
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,3. In an integrated pest management program for a walnut orchard, a PCA observes
increasing resistance of codling moth to organophosphates. Which strategy best aligns
with resistance management principles?
A. Increase the application rate of the organophosphate to overcome resistance.
B. Rotate to a different chemical class with a distinct mode of action and incorporate
mating disruption.
C. Apply the same organophosphate more frequently to prevent sublethal exposure.
D. Switch to a pyrethroid and apply it continuously throughout the season.
Answer: B. Rotate to a different chemical class with a distinct mode of action and
incorporate mating disruption.
Rationale: Resistance management requires rotating modes of action and integrating
non-chemical tactics like mating disruption. Options A, C, and D increase selection
pressure and may lead to cross-resistance or environmental harm.
4. A sprayer is calibrated to deliver 20 gallons per acre at a speed of 4 mph with a
20-foot swath. If the applicator increases speed to 5 mph without adjusting nozzle
pressure, what is the new application rate in gallons per acre?
A. 16
B. 20
C. 25
D. 30
Answer: A. 16
Rationale: Application rate is inversely proportional to speed: 20 GPA × (4 mph / 5 mph) =
16 GPA. Options B, C, and D reflect incorrect proportional reasoning or direct rather than
inverse relationships.
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, 5. A pesticide spill of 5 gallons of a moderately toxic liquid occurs on a concrete pad.
According to California regulations, which action is required first?
A. Evacuate all personnel and notify the county agricultural commissioner immediately.
B. Contain the spill using absorbent materials and prevent it from entering drains or
waterways.
C. Wash the spill into a drainage ditch with water to dilute it.
D. Cover the spill with soil and continue work.
Answer: B. Contain the spill using absorbent materials and prevent it from entering
drains or waterways.
Rationale: The first priority is containment to prevent environmental contamination;
notification follows. Options A, C, and D either delay containment, cause water pollution,
or are illegal.
6. Which of the following best explains the phenomenon of pesticide 'carryover' injury
to a sensitive crop planted 12 months after application of a soil-applied herbicide?
A. The herbicide volatilized and re-deposited on the new crop.
B. The herbicide persisted in soil due to high organic matter and low microbial
degradation.
C. The herbicide leached into groundwater and was taken up by the new crop.
D. The herbicide was applied at a lower rate than labeled, causing incomplete
degradation.
Answer: B. The herbicide persisted in soil due to high organic matter and low
microbial degradation.
Rationale: Carryover occurs when a herbicide persists in soil, often due to factors like high
organic matter, low pH, or reduced microbial activity. Volatilization (A) causes drift,
leaching (C) moves to groundwater, and low rate (D) would reduce persistence.
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