IOWA HERBICIDE RIGHT OF WAY CATEGORY 6
EXAMINATION TEST 2026 QUESTIONS WITH
SOLUTIONS GRADED A+
◉ Both B and C. Answer: Which procedures will help reduce herbicide
drift?
A. Increasing spray pressure
B. Reducing spray pressure
C. Hanging nozzles to a type which emits larger droplets
D. Reducing height of boom
E. Both B and C
◉ They do not damage grasses. Answer: Phenoxy herbicides are widely
used along roadsides because:
A. They are effective on a wide variety of broadleaf and woody species
B. They rarely damage plants in adjacent areas
C. They are high in human toxicity
D. They do not damage grasses
E. Both A and D
,◉ Dichlobenil. Answer: Which of the following nonselective herbicides
has the longest period of control, when used at a given site:
A. Bromacil
B. Dichlobenil
C. Prometon
D. Tebuthiuron
◉ During early flowering. Answer: When is the best time to treat many
perennials developing from an established root system?
◉ Outside an area equal to twice the height of the desirable trees.
Answer: In order to avoid injury to nearby desirable trees; persistent,
nonselective herbicides such as Hyvar should be applied:
A. Only in the fall
B. Outside the drip line of the desirable trees
C. At least 10 feet from the desirable trees
D. Outside an area equal to twice the height of the desirable trees
E. A minimum of 1/2 mile from the desirable trees
◉ The bark prevents penetration of the herbicide and reduces
effectiveness. Answer: Basal bark treatment is not recommended for
wood species larger than 6" in diameter because:
A. The bark prevents penetration of the herbicide and reduces
effectiveness
, B. The cost is prohibitive
C. There is a high risk of drift
D. None of the above
◉ They can damage desirable plants at very low rates, making them
susceptible to drift damage. Answer: A major disadvantage of the
phenoxy-herbicides is:
A. They are non-selective herbicides
B. They can damage desirable plants at very low rates, making them
susceptible to drift damage
C. They are highly toxic to wildlife
D. They persist in the soil for several years
◉ Little effect is seen the year of application. Answer: Krenite is
different from most brush herbicides because:
A. It can be applied either to the foliage or the soil
B. Little effect is seen the year of application
C. Both A and B
D. None of the above
◉ Wettable powders. Answer: Which of the following formulations do
not dissolve in water?
A. Wettable powders
EXAMINATION TEST 2026 QUESTIONS WITH
SOLUTIONS GRADED A+
◉ Both B and C. Answer: Which procedures will help reduce herbicide
drift?
A. Increasing spray pressure
B. Reducing spray pressure
C. Hanging nozzles to a type which emits larger droplets
D. Reducing height of boom
E. Both B and C
◉ They do not damage grasses. Answer: Phenoxy herbicides are widely
used along roadsides because:
A. They are effective on a wide variety of broadleaf and woody species
B. They rarely damage plants in adjacent areas
C. They are high in human toxicity
D. They do not damage grasses
E. Both A and D
,◉ Dichlobenil. Answer: Which of the following nonselective herbicides
has the longest period of control, when used at a given site:
A. Bromacil
B. Dichlobenil
C. Prometon
D. Tebuthiuron
◉ During early flowering. Answer: When is the best time to treat many
perennials developing from an established root system?
◉ Outside an area equal to twice the height of the desirable trees.
Answer: In order to avoid injury to nearby desirable trees; persistent,
nonselective herbicides such as Hyvar should be applied:
A. Only in the fall
B. Outside the drip line of the desirable trees
C. At least 10 feet from the desirable trees
D. Outside an area equal to twice the height of the desirable trees
E. A minimum of 1/2 mile from the desirable trees
◉ The bark prevents penetration of the herbicide and reduces
effectiveness. Answer: Basal bark treatment is not recommended for
wood species larger than 6" in diameter because:
A. The bark prevents penetration of the herbicide and reduces
effectiveness
, B. The cost is prohibitive
C. There is a high risk of drift
D. None of the above
◉ They can damage desirable plants at very low rates, making them
susceptible to drift damage. Answer: A major disadvantage of the
phenoxy-herbicides is:
A. They are non-selective herbicides
B. They can damage desirable plants at very low rates, making them
susceptible to drift damage
C. They are highly toxic to wildlife
D. They persist in the soil for several years
◉ Little effect is seen the year of application. Answer: Krenite is
different from most brush herbicides because:
A. It can be applied either to the foliage or the soil
B. Little effect is seen the year of application
C. Both A and B
D. None of the above
◉ Wettable powders. Answer: Which of the following formulations do
not dissolve in water?
A. Wettable powders
