1|Page
Oregon Pesticide Examination: Ornamental and Turf
Herbicide Exam Questions & Answers | Latest Already
Graded A+ |Questions with Correct Answers 2026 latest
update!!
1. What is the primary purpose of an herbicide?
A. Control unwanted plants (weeds)
B. Control insects
C. Control fungi
D. Increase soil pH
Answer: A
Rationale: Herbicides are pesticides specifically designed to control or
suppress unwanted vegetation.
2. A selective herbicide is designed to:
A. Kill all plants it contacts
B. Control certain plant species while leaving others relatively
unharmed
C. Control only insects
D. Improve fertilizer efficiency
Answer: B
pg. 1
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Rationale: Selective herbicides target specific weeds without
significantly injuring desired turfgrass or ornamental plants when used
properly.
3. Which type of herbicide is applied before weed seeds germinate?
A. Postemergence herbicide
B. Contact herbicide
C. Preemergence herbicide
D. Systemic herbicide
Answer: C
Rationale: Preemergence herbicides prevent weed establishment by
affecting germinating seeds or seedlings.
4. A postemergence herbicide is applied:
A. After weeds have emerged and are actively growing
B. Before planting only
C. During seed storage
D. After harvest exclusively
Answer: A
Rationale: Postemergence herbicides are used on visible weeds.
pg. 2
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5. Which herbicide type moves throughout the plant after absorption?
A. Contact herbicide
B. Systemic herbicide
C. Soil sterilant
D. Adjuvant
Answer: B
Rationale: Systemic herbicides are translocated within the plant to
control roots and shoots.
6. What is a common characteristic of contact herbicides?
A. They affect only the plant tissue contacted by the spray
B. They move extensively through roots
C. They remain active for years
D. They act as fertilizers
Answer: A
Rationale: Contact herbicides kill treated plant tissues but usually do
not move throughout the plant.
7. Which factor most influences herbicide effectiveness?
A. Correct timing and application
B. Color of equipment
pg. 3
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C. Manufacturer location
D. Operator age
Answer: A
Rationale: Proper timing, rate, and application technique are critical for
successful weed control.
8. What does the term "drift" mean?
A. Movement of pesticide away from the target site
B. Breakdown of herbicide in soil
C. Mixing pesticides together
D. Irrigating after application
Answer: A
Rationale: Drift can damage desirable plants and create environmental
concerns.
9. Which weather condition increases the risk of spray drift?
A. High winds
B. Calm conditions
C. Moderate humidity
D. Cloudy skies only
pg. 4
Oregon Pesticide Examination: Ornamental and Turf
Herbicide Exam Questions & Answers | Latest Already
Graded A+ |Questions with Correct Answers 2026 latest
update!!
1. What is the primary purpose of an herbicide?
A. Control unwanted plants (weeds)
B. Control insects
C. Control fungi
D. Increase soil pH
Answer: A
Rationale: Herbicides are pesticides specifically designed to control or
suppress unwanted vegetation.
2. A selective herbicide is designed to:
A. Kill all plants it contacts
B. Control certain plant species while leaving others relatively
unharmed
C. Control only insects
D. Improve fertilizer efficiency
Answer: B
pg. 1
,2|Page
Rationale: Selective herbicides target specific weeds without
significantly injuring desired turfgrass or ornamental plants when used
properly.
3. Which type of herbicide is applied before weed seeds germinate?
A. Postemergence herbicide
B. Contact herbicide
C. Preemergence herbicide
D. Systemic herbicide
Answer: C
Rationale: Preemergence herbicides prevent weed establishment by
affecting germinating seeds or seedlings.
4. A postemergence herbicide is applied:
A. After weeds have emerged and are actively growing
B. Before planting only
C. During seed storage
D. After harvest exclusively
Answer: A
Rationale: Postemergence herbicides are used on visible weeds.
pg. 2
,3|Page
5. Which herbicide type moves throughout the plant after absorption?
A. Contact herbicide
B. Systemic herbicide
C. Soil sterilant
D. Adjuvant
Answer: B
Rationale: Systemic herbicides are translocated within the plant to
control roots and shoots.
6. What is a common characteristic of contact herbicides?
A. They affect only the plant tissue contacted by the spray
B. They move extensively through roots
C. They remain active for years
D. They act as fertilizers
Answer: A
Rationale: Contact herbicides kill treated plant tissues but usually do
not move throughout the plant.
7. Which factor most influences herbicide effectiveness?
A. Correct timing and application
B. Color of equipment
pg. 3
, 4|Page
C. Manufacturer location
D. Operator age
Answer: A
Rationale: Proper timing, rate, and application technique are critical for
successful weed control.
8. What does the term "drift" mean?
A. Movement of pesticide away from the target site
B. Breakdown of herbicide in soil
C. Mixing pesticides together
D. Irrigating after application
Answer: A
Rationale: Drift can damage desirable plants and create environmental
concerns.
9. Which weather condition increases the risk of spray drift?
A. High winds
B. Calm conditions
C. Moderate humidity
D. Cloudy skies only
pg. 4
