Iowa 3OT Pesticide Manual Study Guide Exam Latest
2026/2027 Updated Verified Questions and Solutions A+ Pass
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Define pesticide
Any material used to kill, attract, repel, regulate, or interrupt growth and
mating of pests, or to regulate plant growth
Contact pesticides
Must physically touch the pest organism or be sprayed on the site the pest
frequents to exert an action
Example would be protective fungicide
Must be re-applied to new plant tissues or if precipitation washes product off
Systemic pesticide
Enters the plant via roots or above ground plant tissues and is moved inside of
the plant.
Could render plant toxic to insect or mice
Could move through plant to kill parts of the plant
Example would be curative fungicide because it penetrates the plant and
stops disease
,Preemergence
Applied prior to weed seed germination.
Little to no effect on weeds that have emerged
Postemergence
Applied to actively growing plants.
Work best in sunlight, high humidity, good soil moisture
Selective pesticide
Control only certain types or stages of pests while leaving nontarget
organisms unaffected.
Example would be herbicide that kills broadleaf weeds and not turfgrass
Nonselective pesticide
Exert their action on a wide variety of pests.
Control most of the plants they are sprayed
on.
,Identify the best application timing for effective pest control as it pertains to:
plant diseases, insects, and weeds
Plant diseases
For fungicides, it is critical that susceptible tissues be protected before an
infection begins or at the first appearance of any symptoms
Insects
The younger the stage of insect, the more susceptible it is to chemical control.
Weeds
Generally most effective when applied to actively growing plants and least
effective when plants are not actively growing
Annual weeds are easiest to control in early spring
Biennials should be treated in fall or early spring when in the rosette
stage Perennial weeds can be controlled in early bloom stage or in
the fall
, Explain how pesticide resistance develops in a pest population
Resistance is the ability of a pest species that was once effectively controlled
by a pesticide to survive spray concentrations that were previously effective.
It is an inherited trait that results from repeated applications of pesticides
with the same site of action or mode of action.
Examples include pythium blight in turfgrass, botrytis in ornamental, green
peach aphid in insects, and goosegrass weeds
State the importance of the numeric codes at the top of a pesticide label
and pesticide resistance
These codes help applicators quickly identify the mode of action by looking at
the group number.
Varying this can help reduce resistance
State four ways to minimize pesticide drift
Correctly chosen
nozzle Reduced
spray pressure
Monitor weather conditions
Keeping the spray nozzle near the target
Summarize the ways in which pesticides can injure nontarget plants
Contact can kill or injure plants
Movement into the root zone where it can be absorbed is also bad
2026/2027 Updated Verified Questions and Solutions A+ Pass
Guaranteed
Define pesticide
Any material used to kill, attract, repel, regulate, or interrupt growth and
mating of pests, or to regulate plant growth
Contact pesticides
Must physically touch the pest organism or be sprayed on the site the pest
frequents to exert an action
Example would be protective fungicide
Must be re-applied to new plant tissues or if precipitation washes product off
Systemic pesticide
Enters the plant via roots or above ground plant tissues and is moved inside of
the plant.
Could render plant toxic to insect or mice
Could move through plant to kill parts of the plant
Example would be curative fungicide because it penetrates the plant and
stops disease
,Preemergence
Applied prior to weed seed germination.
Little to no effect on weeds that have emerged
Postemergence
Applied to actively growing plants.
Work best in sunlight, high humidity, good soil moisture
Selective pesticide
Control only certain types or stages of pests while leaving nontarget
organisms unaffected.
Example would be herbicide that kills broadleaf weeds and not turfgrass
Nonselective pesticide
Exert their action on a wide variety of pests.
Control most of the plants they are sprayed
on.
,Identify the best application timing for effective pest control as it pertains to:
plant diseases, insects, and weeds
Plant diseases
For fungicides, it is critical that susceptible tissues be protected before an
infection begins or at the first appearance of any symptoms
Insects
The younger the stage of insect, the more susceptible it is to chemical control.
Weeds
Generally most effective when applied to actively growing plants and least
effective when plants are not actively growing
Annual weeds are easiest to control in early spring
Biennials should be treated in fall or early spring when in the rosette
stage Perennial weeds can be controlled in early bloom stage or in
the fall
, Explain how pesticide resistance develops in a pest population
Resistance is the ability of a pest species that was once effectively controlled
by a pesticide to survive spray concentrations that were previously effective.
It is an inherited trait that results from repeated applications of pesticides
with the same site of action or mode of action.
Examples include pythium blight in turfgrass, botrytis in ornamental, green
peach aphid in insects, and goosegrass weeds
State the importance of the numeric codes at the top of a pesticide label
and pesticide resistance
These codes help applicators quickly identify the mode of action by looking at
the group number.
Varying this can help reduce resistance
State four ways to minimize pesticide drift
Correctly chosen
nozzle Reduced
spray pressure
Monitor weather conditions
Keeping the spray nozzle near the target
Summarize the ways in which pesticides can injure nontarget plants
Contact can kill or injure plants
Movement into the root zone where it can be absorbed is also bad
