IOWA COMMERCIAL PESTICIDE APPLICATOR EXAM LATEST 2026
UPDATED QUESTIONS AND VERIFIED 100% SOLUTIONS (2026/2027)
|A+ GRADED |GUARANTEED PASS
What is essential when using contact herbicides? - Answers -Good spray coverage (usually
involving high carrier volumes)
When is the best time (in regards to maximum weed control) to apply contact herbicides to
annual weeds? - Answers -When the weeds are small and actively growing
Why are contact herbicides not great at controlling perennial weeds? - Answers -They only
control the shoot, and cannot travel down to kill the root system resulting in regrowth
When you are using translocated herbicides to control perennial weed root systems, when is
usually the best treatment time? - Answers -Bud to bloom growth stage
When applying Prowl, Banvel, and Clarity in a corn crop, what practice can cause injury -
Answers -Incorporation
Why shouldn't you apply 2,4-D to corn from tasseling to brown silk? - Answers -Severe
pollination injury can occur
When does particle drift occur? - Answers -Small spray droplets move off target when they are
applied, typically due to wind
1|Page
, How can you reduce particle drift? - Answers -Use coarse sprays and drift control agents while
avoiding application during windy conditions
Which formulation of 2,4-D can drift in vapor form and which cannot? - Answers -Ester 2,4-D
can vapor drift
Amine 2,4-D cannot
Why does Banvel have the possibility to vapor drift after it has been applied? - Answers -Banvel
changes to volatile forms on plant leaves
In Iowa, when is the general time of year when temperatures rise too high to apply Banvel -
Answers -Mid-June
At above what approximate temperature does Banvel and ester based 2,4-D have increased risk
of vapor drift? - Answers -85 (f)
Why is Gramoxone Extra a restricted-use pesticide? - Answers -It is relatively high in toxicity to
humans with an LD50 of 120 mg/kg
2|Page
UPDATED QUESTIONS AND VERIFIED 100% SOLUTIONS (2026/2027)
|A+ GRADED |GUARANTEED PASS
What is essential when using contact herbicides? - Answers -Good spray coverage (usually
involving high carrier volumes)
When is the best time (in regards to maximum weed control) to apply contact herbicides to
annual weeds? - Answers -When the weeds are small and actively growing
Why are contact herbicides not great at controlling perennial weeds? - Answers -They only
control the shoot, and cannot travel down to kill the root system resulting in regrowth
When you are using translocated herbicides to control perennial weed root systems, when is
usually the best treatment time? - Answers -Bud to bloom growth stage
When applying Prowl, Banvel, and Clarity in a corn crop, what practice can cause injury -
Answers -Incorporation
Why shouldn't you apply 2,4-D to corn from tasseling to brown silk? - Answers -Severe
pollination injury can occur
When does particle drift occur? - Answers -Small spray droplets move off target when they are
applied, typically due to wind
1|Page
, How can you reduce particle drift? - Answers -Use coarse sprays and drift control agents while
avoiding application during windy conditions
Which formulation of 2,4-D can drift in vapor form and which cannot? - Answers -Ester 2,4-D
can vapor drift
Amine 2,4-D cannot
Why does Banvel have the possibility to vapor drift after it has been applied? - Answers -Banvel
changes to volatile forms on plant leaves
In Iowa, when is the general time of year when temperatures rise too high to apply Banvel -
Answers -Mid-June
At above what approximate temperature does Banvel and ester based 2,4-D have increased risk
of vapor drift? - Answers -85 (f)
Why is Gramoxone Extra a restricted-use pesticide? - Answers -It is relatively high in toxicity to
humans with an LD50 of 120 mg/kg
2|Page
