Iowa
Iowa Commercial Pesticide Applicator
Category1A
What is the greatest hazard when applying most herbicides? - ANS Injury to
nontargetplants
Name some herbicides which are very effective against germinatingweeds but
less effectiveon establishedweeds.- ANS Frontier, Lasso, and Dual
What soil conditions reduce the activityof manyherbicides and require increased
rates for adequateweed control? - ANS Higher levels of soil organic matteror
clay
Two herbicides which are more active on soils with a pH above 7.5and can injure
soybeans - ANS Sencor and Lexone
Where are high pH soils most common in Iowa? - ANS Next to limestone and
gravelroads
Two herbicides that are more persistent and likely to carryover residues. - ANS
Atrazineand chlorimuron
What factors can increase chances of herbicide carryover? - ANS Dry weather,
high rates,late application,and in the case of some herbicides,high soil pH
Can additive injury occur when applying Sencor/Lexone on soybeans in fields
with atrazinecarryoverresidues? - ANS Yes
Iowa Commercial Pesticide Applicator Category 1A
, Iowa
What do preemergence herbicides rely on to move the herbicide into the weed
seed germination zone (top 1/2-1 inch) of soil? - ANS Rainfall or irrigation
What tillage tools will improve weed control when rainfall does not occur soon
after herbicide application, and weeds begin emerging? - ANS Rotary Hoe and
Harrow
Name 3 herbicides which must be incorporated to prevent evaporation loss. -
ANS Sultan+,Eradicane,EradicaneExtra
Define photodecomposition- ANS Chemical breakdown caused by exposure to
Name two herbicides thatmust be incorporatedto preventphotodecomposition.-
ANS Treflan, Sonalan
Why are Basagran, Blazer, Buctril, Poast Plus, and Fusilade 2000 only applied
postemergence?- ANS They have little or no soil activity
Are Roundup and Gramoxone Extra selective or nonselectiveherbicides? - ANS
Nonselective
Blazer, Basagran, Buctril, and Gramoxone Extra contact herbicides or
translocatedherbicides? - ANS Contact herbicides
Define translocated herbicides - ANS Herbicides which move in the phloem of
plants
Iowa Commercial Pesticide Applicator Category 1A
Iowa Commercial Pesticide Applicator
Category1A
What is the greatest hazard when applying most herbicides? - ANS Injury to
nontargetplants
Name some herbicides which are very effective against germinatingweeds but
less effectiveon establishedweeds.- ANS Frontier, Lasso, and Dual
What soil conditions reduce the activityof manyherbicides and require increased
rates for adequateweed control? - ANS Higher levels of soil organic matteror
clay
Two herbicides which are more active on soils with a pH above 7.5and can injure
soybeans - ANS Sencor and Lexone
Where are high pH soils most common in Iowa? - ANS Next to limestone and
gravelroads
Two herbicides that are more persistent and likely to carryover residues. - ANS
Atrazineand chlorimuron
What factors can increase chances of herbicide carryover? - ANS Dry weather,
high rates,late application,and in the case of some herbicides,high soil pH
Can additive injury occur when applying Sencor/Lexone on soybeans in fields
with atrazinecarryoverresidues? - ANS Yes
Iowa Commercial Pesticide Applicator Category 1A
, Iowa
What do preemergence herbicides rely on to move the herbicide into the weed
seed germination zone (top 1/2-1 inch) of soil? - ANS Rainfall or irrigation
What tillage tools will improve weed control when rainfall does not occur soon
after herbicide application, and weeds begin emerging? - ANS Rotary Hoe and
Harrow
Name 3 herbicides which must be incorporated to prevent evaporation loss. -
ANS Sultan+,Eradicane,EradicaneExtra
Define photodecomposition- ANS Chemical breakdown caused by exposure to
Name two herbicides thatmust be incorporatedto preventphotodecomposition.-
ANS Treflan, Sonalan
Why are Basagran, Blazer, Buctril, Poast Plus, and Fusilade 2000 only applied
postemergence?- ANS They have little or no soil activity
Are Roundup and Gramoxone Extra selective or nonselectiveherbicides? - ANS
Nonselective
Blazer, Basagran, Buctril, and Gramoxone Extra contact herbicides or
translocatedherbicides? - ANS Contact herbicides
Define translocated herbicides - ANS Herbicides which move in the phloem of
plants
Iowa Commercial Pesticide Applicator Category 1A
